72640687 has 24 divisors (see below), whose sum is σ = 87390576. Its totient is φ = 60173568.

The previous prime is 72640661. The next prime is 72640703. The reversal of 72640687 is 78604627.

It is not a de Polignac number, because 72640687 - 2¹¹ = 72638639 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72640637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 215383 + ... + 215719.

It is an arithmetic number, because the mean of its divisors is an integer number (3641274).

Almost surely, 2^72640687 is an apocalyptic number.

72640687 is a deficient number, since it is larger than the sum of its proper divisors (14749889).

72640687 is a wasteful number, since it uses less digits than its factorization.

72640687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 487 (or 480 counting only the distinct ones).

The product of its (nonzero) digits is 112896, while the sum is 40.

The square root of 72640687 is about 8522.9506041042. The cubic root of 72640687 is about 417.2470879092.

The spelling of 72640687 in words is "seventy-two million, six hundred forty thousand, six hundred eighty-seven".