28656879720 has 96 divisors (see below), whose sum is σ = 100006682400. Its totient is φ = 6550142592.

The previous prime is 28656879703. The next prime is 28656879721. The reversal of 28656879720 is 2797865682.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is not an unprimeable number, because it can be changed into a prime (28656879721) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2430930 + ... + 2442689.

It is an arithmetic number, because the mean of its divisors is an integer number (1041736275).

Almost surely, 2^28656879720 is an apocalyptic number.

28656879720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28656879720 is an abundant number, since it is smaller than the sum of its proper divisors (71349802680).

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

28656879720 is a wasteful number, since it uses less digits than its factorization.

28656879720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4873647 (or 4873636 counting only the distinct ones).

The product of its (nonzero) digits is 20321280, while the sum is 60.

The spelling of 28656879720 in words is "twenty-eight billion, six hundred fifty-six million, eight hundred seventy-nine thousand, seven hundred twenty".