72545731 has 2 divisors, whose sum is σ = 72545732. Its totient is φ = 72545730.

The previous prime is 72545723. The next prime is 72545761. The reversal of 72545731 is 13754527.

It is a weak prime.

It is an emirp because it is prime and its reverse (13754527) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72545731 - 2³ = 72545723 is a prime.

It is a super-2 number, since 2×72545731² = 10525766172648722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (72545701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36272865 + 36272866.

It is an arithmetic number, because the mean of its divisors is an integer number (36272866).

Almost surely, 2^72545731 is an apocalyptic number.

72545731 is a deficient number, since it is larger than the sum of its proper divisors (1).

72545731 is an equidigital number, since it uses as much as digits as its factorization.

72545731 is an evil number, because the sum of its binary digits is even.

The product of its digits is 29400, while the sum is 34.

The square root of 72545731 is about 8517.3781764109. The cubic root of 72545731 is about 417.0651999871.

The spelling of 72545731 in words is "seventy-two million, five hundred forty-five thousand, seven hundred thirty-one".