28915915 has 8 divisors (see below), whose sum is σ = 39656160. Its totient is φ = 19828032.

The previous prime is 28915897. The next prime is 28915919. The reversal of 28915915 is 51951982.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28915915 - 2¹⁷ = 28784843 is a prime.

It is a super-2 number, since 2×28915915² = 1672260280574450, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28915919) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 413050 + ... + 413119.

It is an arithmetic number, because the mean of its divisors is an integer number (4957020).

Almost surely, 2^28915915 is an apocalyptic number.

28915915 is a deficient number, since it is larger than the sum of its proper divisors (10740245).

28915915 is an equidigital number, since it uses as much as digits as its factorization.

28915915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 826181.

The product of its digits is 32400, while the sum is 40.

The square root of 28915915 is about 5377.3520435248. The cubic root of 28915915 is about 306.9344574614.

The spelling of 28915915 in words is "twenty-eight million, nine hundred fifteen thousand, nine hundred fifteen".