72639231 has 16 divisors (see below), whose sum is σ = 114259968. Its totient is φ = 40168800.

The previous prime is 72639211. The next prime is 72639239. The reversal of 72639231 is 13293627.

It is a happy number.

It is not a de Polignac number, because 72639231 - 2¹⁰ = 72638207 is a prime.

It is a super-2 number, since 2×72639231² = 10552915760542722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 72639192 and 72639201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72639239) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55140 + ... + 56441.

It is an arithmetic number, because the mean of its divisors is an integer number (7141248).

Almost surely, 2^72639231 is an apocalyptic number.

72639231 is a deficient number, since it is larger than the sum of its proper divisors (41620737).

72639231 is a wasteful number, since it uses less digits than its factorization.

72639231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111622.

The product of its digits is 13608, while the sum is 33.

The square root of 72639231 is about 8522.8651872478. The cubic root of 72639231 is about 417.2443001427.

The spelling of 72639231 in words is "seventy-two million, six hundred thirty-nine thousand, two hundred thirty-one".