72389531 has 2 divisors, whose sum is σ = 72389532. Its totient is φ = 72389530.

The previous prime is 72389503. The next prime is 72389549. The reversal of 72389531 is 13598327.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72389531 is a prime.

It is a super-2 number, since 2×72389531² = 10480488396799922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (72389561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36194765 + 36194766.

It is an arithmetic number, because the mean of its divisors is an integer number (36194766).

Almost surely, 2^72389531 is an apocalyptic number.

72389531 is a deficient number, since it is larger than the sum of its proper divisors (1).

72389531 is an equidigital number, since it uses as much as digits as its factorization.

72389531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45360, while the sum is 38.

The square root of 72389531 is about 8508.2037469727. The cubic root of 72389531 is about 416.7656537796.

The spelling of 72389531 in words is "seventy-two million, three hundred eighty-nine thousand, five hundred thirty-one".