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1215420 = 223547431
BaseRepresentation
bin100101000101110111100
32021202020120
410220232330
5302343140
642014540
713221333
oct4505674
92252216
101215420
11760188
124a7450
133372ab
14238d1a
151901d0
hex128bbc

1215420 has 48 divisors (see below), whose sum is σ = 3483648. Its totient is φ = 316480.

The previous prime is 1215407. The next prime is 1215421. The reversal of 1215420 is 245121.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 1215420.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2605 + ... + 3035.

It is an arithmetic number, because the mean of its divisors is an integer number (72576).

21215420 is an apocalyptic number.

1215420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1215420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1741824).

1215420 is an abundant number, since it is smaller than the sum of its proper divisors (2268228).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1215420 is a wasteful number, since it uses less digits than its factorization.

1215420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 490 (or 488 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 1215420 is about 1102.4608836598. The cubic root of 1215420 is about 106.7190931519.

Subtracting from 1215420 its reverse (245121), we obtain a cube (970299 = 993).

The spelling of 1215420 in words is "one million, two hundred fifteen thousand, four hundred twenty".

Divisors: 1 2 3 4 5 6 10 12 15 20 30 47 60 94 141 188 235 282 431 470 564 705 862 940 1293 1410 1724 2155 2586 2820 4310 5172 6465 8620 12930 20257 25860 40514 60771 81028 101285 121542 202570 243084 303855 405140 607710 1215420