28690872 has 96 divisors (see below), whose sum is σ = 86238720. Its totient is φ = 7922880.

The previous prime is 28690819. The next prime is 28690877. The reversal of 28690872 is 27809682.

It is a happy number.

It is a super-2 number, since 2×28690872² = 1646332272240768, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28690877) 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, 36063 + ... + 36849.

It is an arithmetic number, because the mean of its divisors is an integer number (898320).

Almost surely, 2^28690872 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 28690872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43119360).

28690872 is an abundant number, since it is smaller than the sum of its proper divisors (57547848).

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

28690872 is a wasteful number, since it uses less digits than its factorization.

28690872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 841 (or 830 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 42.

The square root of 28690872 is about 5356.3860951205. The cubic root of 28690872 is about 306.1361263708.

It can be divided in two parts, 28 and 690872, that added together give a triangular number (690900 = T₁₁₇₅).

The spelling of 28690872 in words is "twenty-eight million, six hundred ninety thousand, eight hundred seventy-two".