72136431 has 12 divisors (see below), whose sum is σ = 104323752. Its totient is φ = 48032496.

The previous prime is 72136397. The next prime is 72136433. The reversal of 72136431 is 13463127.

72136431 is a `hidden beast` number, since 7 + 2 + 13 + 643 + 1 = 666.

It is not a de Polignac number, because 72136431 - 2¹⁰ = 72135407 is a prime.

It is a super-2 number, since 2×72136431² = 10407329354835522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 72136395 and 72136404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72136433) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3745 + ... + 12581.

It is an arithmetic number, because the mean of its divisors is an integer number (8693646).

Almost surely, 2^72136431 is an apocalyptic number.

72136431 is a deficient number, since it is larger than the sum of its proper divisors (32187321).

72136431 is a wasteful number, since it uses less digits than its factorization.

72136431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9750 (or 9747 counting only the distinct ones).

The product of its digits is 3024, while the sum is 27.

The square root of 72136431 is about 8493.3168432598. The cubic root of 72136431 is about 416.2793654039.

Adding to 72136431 its reverse (13463127), we get a palindrome (85599558).

It can be divided in two parts, 72 and 136431, that added together give a triangular number (136503 = T₅₂₂).

The spelling of 72136431 in words is "seventy-two million, one hundred thirty-six thousand, four hundred thirty-one".