28207656 has 64 divisors (see below), whose sum is σ = 80203200. Its totient is φ = 9180864.

The previous prime is 28207651. The next prime is 28207693. The reversal of 28207656 is 65670282.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 28207656.

It is not an unprimeable number, because it can be changed into a prime (28207651) 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, 7770 + ... + 10806.

It is an arithmetic number, because the mean of its divisors is an integer number (1253175).

Almost surely, 2^28207656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28207656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40101600).

28207656 is an abundant number, since it is smaller than the sum of its proper divisors (51995544).

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

28207656 is a wasteful number, since it uses less digits than its factorization.

28207656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3095 (or 3085 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 28207656 is about 5311.0880241246. The cubic root of 28207656 is about 304.4077227727.

The spelling of 28207656 in words is "twenty-eight million, two hundred seven thousand, six hundred fifty-six".