28391567924 has 12 divisors (see below), whose sum is σ = 50365864164. Its totient is φ = 14001321024.

The previous prime is 28391567887. The next prime is 28391567929. The reversal of 28391567924 is 42976519382.

It can be written as a sum of positive squares in 2 ways, for example, as 11887540900 + 16504027024 = 109030^2 + 128468^2 .

It is a super-2 number, since 2×28391567924² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28391567924.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28391567929) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48615407 + ... + 48615990.

It is an arithmetic number, because the mean of its divisors is an integer number (4197155347).

Almost surely, 2^28391567924 is an apocalyptic number.

It is an amenable number.

28391567924 is a deficient number, since it is larger than the sum of its proper divisors (21974296240).

28391567924 is a wasteful number, since it uses less digits than its factorization.

28391567924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97231474 (or 97231472 counting only the distinct ones).

The product of its digits is 6531840, while the sum is 56.

The spelling of 28391567924 in words is "twenty-eight billion, three hundred ninety-one million, five hundred sixty-seven thousand, nine hundred twenty-four".