72561505 has 16 divisors (see below), whose sum is σ = 89812800. Its totient is φ = 56250688.

The previous prime is 72561497. The next prime is 72561521. The reversal of 72561505 is 50516527.

It is a cyclic number.

It is not a de Polignac number, because 72561505 - 2³ = 72561497 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20346 + ... + 23644.

It is an arithmetic number, because the mean of its divisors is an integer number (5613300).

Almost surely, 2^72561505 is an apocalyptic number.

It is an amenable number.

72561505 is a deficient number, since it is larger than the sum of its proper divisors (17251295).

72561505 is a wasteful number, since it uses less digits than its factorization.

72561505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3440.

The product of its (nonzero) digits is 10500, while the sum is 31.

The square root of 72561505 is about 8518.3041152567. The cubic root of 72561505 is about 417.0954260234.

The spelling of 72561505 in words is "seventy-two million, five hundred sixty-one thousand, five hundred five".