28725915 has 32 divisors (see below), whose sum is σ = 47275776. Its totient is φ = 14889600.

The previous prime is 28725911. The next prime is 28725923. The reversal of 28725915 is 51952782.

It is not a de Polignac number, because 28725915 - 2² = 28725911 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28725911) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 101364 + ... + 101646.

It is an arithmetic number, because the mean of its divisors is an integer number (1477368).

Almost surely, 2^28725915 is an apocalyptic number.

28725915 is a deficient number, since it is larger than the sum of its proper divisors (18549861).

28725915 is a wasteful number, since it uses less digits than its factorization.

28725915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 459.

The product of its digits is 50400, while the sum is 39.

The square root of 28725915 is about 5359.6562389765. The cubic root of 28725915 is about 306.2607137721.

The spelling of 28725915 in words is "twenty-eight million, seven hundred twenty-five thousand, nine hundred fifteen".