28515312 has 60 divisors (see below), whose sum is σ = 91206960. Its totient is φ = 8146944.

The previous prime is 28515269. The next prime is 28515353. The reversal of 28515312 is 21351582.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13137 + ... + 15152.

It is an arithmetic number, because the mean of its divisors is an integer number (1520116).

Almost surely, 2^28515312 is an apocalyptic number.

It is an amenable number.

28515312 is an abundant number, since it is smaller than the sum of its proper divisors (62691648).

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

28515312 is a wasteful number, since it uses less digits than its factorization.

28515312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28310 (or 28301 counting only the distinct ones).

The product of its digits is 2400, while the sum is 27.

The square root of 28515312 is about 5339.9730336398. The cubic root of 28515312 is about 305.5104307920.

Adding to 28515312 its reverse (21351582), we get a palindrome (49866894).

The spelling of 28515312 in words is "twenty-eight million, five hundred fifteen thousand, three hundred twelve".