28507738 has 16 divisors (see below), whose sum is σ = 49700160. Its totient is φ = 12010176.

The previous prime is 28507729. The next prime is 28507747. The reversal of 28507738 is 83770582.

It is an interprime number because it is at equal distance from previous prime (28507729) and next prime (28507747).

It is a super-2 number, since 2×28507738² = 1625382251753288, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28507738.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16431 + ... + 18082.

It is an arithmetic number, because the mean of its divisors is an integer number (3106260).

Almost surely, 2^28507738 is an apocalyptic number.

28507738 is a deficient number, since it is larger than the sum of its proper divisors (21192422).

28507738 is a wasteful number, since it uses less digits than its factorization.

28507738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34581.

The product of its (nonzero) digits is 94080, while the sum is 40.

The square root of 28507738 is about 5339.2638069307. The cubic root of 28507738 is about 305.4833793503.

The spelling of 28507738 in words is "twenty-eight million, five hundred seven thousand, seven hundred thirty-eight".