28724784 has 40 divisors (see below), whose sum is σ = 80953152. Its totient is φ = 8704320.

The previous prime is 28724753. The next prime is 28724797. The reversal of 28724784 is 48742782.

It is a super-2 number, since 2×28724784² = 1650226431693312, which contains 22 as substring.

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, 26674 + ... + 27729.

Almost surely, 2^28724784 is an apocalyptic number.

28724784 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

28724784 is an abundant number, since it is smaller than the sum of its proper divisors (52228368).

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

28724784 is a wasteful number, since it uses less digits than its factorization.

28724784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54425 (or 54419 counting only the distinct ones).

The product of its digits is 200704, while the sum is 42.

The square root of 28724784 is about 5359.5507274398. The cubic root of 28724784 is about 306.2566943421.

The spelling of 28724784 in words is "twenty-eight million, seven hundred twenty-four thousand, seven hundred eighty-four".