72646531 has 2 divisors, whose sum is σ = 72646532. Its totient is φ = 72646530.

The previous prime is 72646529. The next prime is 72646603. The reversal of 72646531 is 13564627.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 72646531 - 2¹ = 72646529 is a prime.

It is a super-2 number, since 2×72646531² = 10555036932667922, which contains 22 as substring.

Together with 72646529, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (72640531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36323265 + 36323266.

It is an arithmetic number, because the mean of its divisors is an integer number (36323266).

Almost surely, 2^72646531 is an apocalyptic number.

72646531 is a deficient number, since it is larger than the sum of its proper divisors (1).

72646531 is an equidigital number, since it uses as much as digits as its factorization.

72646531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30240, while the sum is 34.

The square root of 72646531 is about 8523.2934362252. The cubic root of 72646531 is about 417.2582768938.

The spelling of 72646531 in words is "seventy-two million, six hundred forty-six thousand, five hundred thirty-one".