28515491856 has 80 divisors (see below), whose sum is σ = 84490385920. Its totient is φ = 9198541440.

The previous prime is 28515491843. The next prime is 28515491857. The reversal of 28515491856 is 65819451582.

28515491856 is a `hidden beast` number, since 2 + 8 + 515 + 49 + 1 + 85 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (28515491857) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1051255 + ... + 1078038.

It is an arithmetic number, because the mean of its divisors is an integer number (1056129824).

Almost surely, 2^28515491856 is an apocalyptic number.

It is an amenable number.

28515491856 is an abundant number, since it is smaller than the sum of its proper divisors (55974894064).

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

28515491856 is a wasteful number, since it uses less digits than its factorization.

28515491856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2129341 (or 2129329 counting only the distinct ones).

The product of its digits is 3456000, while the sum is 54.

The spelling of 28515491856 in words is "twenty-eight billion, five hundred fifteen million, four hundred ninety-one thousand, eight hundred fifty-six".