28931912 has 8 divisors (see below), whose sum is σ = 54247350. Its totient is φ = 14465952.

The previous prime is 28931911. The next prime is 28931921. The reversal of 28931912 is 21913982.

It can be written as a sum of positive squares in only one way, i.e., 24462916 + 4468996 = 4946^2 + 2114^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-4 number, since 4×28931912⁴ (a number of 31 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (28931911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1808237 + ... + 1808252.

Almost surely, 2^28931912 is an apocalyptic number.

It is an amenable number.

28931912 is a deficient number, since it is larger than the sum of its proper divisors (25315438).

28931912 is a wasteful number, since it uses less digits than its factorization.

28931912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3616495 (or 3616491 counting only the distinct ones).

The product of its digits is 7776, while the sum is 35.

The square root of 28931912 is about 5378.8392799934. The cubic root of 28931912 is about 306.9910482735.

The spelling of 28931912 in words is "twenty-eight million, nine hundred thirty-one thousand, nine hundred twelve".