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28656020 = 2251432801
BaseRepresentation
bin110110101010…
…0000110010100
31222220212200002
41231110012110
524313443040
62502110432
7465400151
oct155240624
958825602
1028656020
11151a2768
12971b418
135c24333
143b3d228
1527b0a15
hex1b54194

28656020 has 12 divisors (see below), whose sum is σ = 60177684. Its totient is φ = 11462400.

The previous prime is 28656013. The next prime is 28656049. The reversal of 28656020 is 2065682.

It can be written as a sum of positive squares in 2 ways, for example, as 18645124 + 10010896 = 4318^2 + 3164^2 .

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 716381 + ... + 716420.

It is an arithmetic number, because the mean of its divisors is an integer number (5014807).

Almost surely, 228656020 is an apocalyptic number.

28656020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28656020 is an abundant number, since it is smaller than the sum of its proper divisors (31521664).

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

28656020 is a wasteful number, since it uses less digits than its factorization.

28656020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1432810 (or 1432808 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 28656020 is about 5353.1317936326. The cubic root of 28656020 is about 306.0121173666.

The spelling of 28656020 in words is "twenty-eight million, six hundred fifty-six thousand, twenty".

Divisors: 1 2 4 5 10 20 1432801 2865602 5731204 7164005 14328010 28656020