23128515 has 48 divisors (see below), whose sum is σ = 42681600. Its totient is φ = 11563776.

The previous prime is 23128507. The next prime is 23128537. The reversal of 23128515 is 51582132.

It is a happy number.

23128515 is a `hidden beast` number, since 23 + 128 + 515 = 666.

It is not a de Polignac number, because 23128515 - 2³ = 23128507 is a prime.

It is a super-2 number, since 2×23128515² = 1069856412210450, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 48046 + ... + 48524.

It is an arithmetic number, because the mean of its divisors is an integer number (889200).

Almost surely, 2^23128515 is an apocalyptic number.

23128515 is a deficient number, since it is larger than the sum of its proper divisors (19553085).

23128515 is a wasteful number, since it uses less digits than its factorization.

23128515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 556 (or 553 counting only the distinct ones).

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

The square root of 23128515 is about 4809.2114738281. The cubic root of 23128515 is about 284.9153950160.

The spelling of 23128515 in words is "twenty-three million, one hundred twenty-eight thousand, five hundred fifteen".