28697915 has 4 divisors (see below), whose sum is σ = 34437504. Its totient is φ = 22958328.

The previous prime is 28697897. The next prime is 28697927. The reversal of 28697915 is 51979682.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51979682 = 2 ⋅25989841.

It is a cyclic number.

It is not a de Polignac number, because 28697915 - 2¹⁴ = 28681531 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28697915.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2869787 + ... + 2869796.

It is an arithmetic number, because the mean of its divisors is an integer number (8609376).

Almost surely, 2^28697915 is an apocalyptic number.

28697915 is a deficient number, since it is larger than the sum of its proper divisors (5739589).

28697915 is an equidigital number, since it uses as much as digits as its factorization.

28697915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5739588.

The product of its digits is 272160, while the sum is 47.

The square root of 28697915 is about 5357.0434943166. The cubic root of 28697915 is about 306.1611742947.

The spelling of 28697915 in words is "twenty-eight million, six hundred ninety-seven thousand, nine hundred fifteen".