Search a number
-
+
28257860 = 2251412893
BaseRepresentation
bin110101111001…
…0111001000100
31222011122111102
41223302321010
524213222420
62445355232
7462121301
oct153627104
958148442
1028257860
1114a50604
129568b18
135b15037
143a780a8
152732a75
hex1af2e44

28257860 has 12 divisors (see below), whose sum is σ = 59341548. Its totient is φ = 11303136.

The previous prime is 28257847. The next prime is 28257907. The reversal of 28257860 is 6875282.

It can be written as a sum of positive squares in 2 ways, for example, as 2876416 + 25381444 = 1696^2 + 5038^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 706427 + ... + 706466.

It is an arithmetic number, because the mean of its divisors is an integer number (4945129).

Almost surely, 228257860 is an apocalyptic number.

28257860 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28257860 is an abundant number, since it is smaller than the sum of its proper divisors (31083688).

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

28257860 is a wasteful number, since it uses less digits than its factorization.

28257860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1412902 (or 1412900 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 38.

The square root of 28257860 is about 5315.8122615457. The cubic root of 28257860 is about 304.5882107423.

The spelling of 28257860 in words is "twenty-eight million, two hundred fifty-seven thousand, eight hundred sixty".

Divisors: 1 2 4 5 10 20 1412893 2825786 5651572 7064465 14128930 28257860