72515775 has 24 divisors (see below), whose sum is σ = 121690624. Its totient is φ = 38095200.

The previous prime is 72515771. The next prime is 72515797. The reversal of 72515775 is 57751527.

It is not a de Polignac number, because 72515775 - 2² = 72515771 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72515771) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2191 + ... + 12240.

Almost surely, 2^72515775 is an apocalyptic number.

72515775 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

72515775 is a deficient number, since it is larger than the sum of its proper divisors (49174849).

72515775 is a wasteful number, since it uses less digits than its factorization.

72515775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14511 (or 14506 counting only the distinct ones).

The product of its digits is 85750, while the sum is 39.

The square root of 72515775 is about 8515.6194724753. The cubic root of 72515775 is about 417.0077864311.

The spelling of 72515775 in words is "seventy-two million, five hundred fifteen thousand, seven hundred seventy-five".