28931715 has 16 divisors (see below), whose sum is σ = 51434400. Its totient is φ = 15430176.

The previous prime is 28931681. The next prime is 28931759. The reversal of 28931715 is 51713982.

It is not a de Polignac number, because 28931715 - 2¹³ = 28923523 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28931715.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 107020 + ... + 107289.

It is an arithmetic number, because the mean of its divisors is an integer number (3214650).

Almost surely, 2^28931715 is an apocalyptic number.

28931715 is a deficient number, since it is larger than the sum of its proper divisors (22502685).

28931715 is a wasteful number, since it uses less digits than its factorization.

28931715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214323 (or 214317 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 28931715 is about 5378.8209674612. The cubic root of 28931715 is about 306.9903514954.

It can be divided in two parts, 28931 and 715, that added together give a triangular number (29646 = T₂₄₃).

The spelling of 28931715 in words is "twenty-eight million, nine hundred thirty-one thousand, seven hundred fifteen".