72797731 has 2 divisors, whose sum is σ = 72797732. Its totient is φ = 72797730.

The previous prime is 72797713. The next prime is 72797741. The reversal of 72797731 is 13779727.

It is a happy number.

Together with previous prime (72797713) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 72797731 - 2¹⁵ = 72764963 is a prime.

It is a super-2 number, since 2×72797731² = 10599019277496722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (72797741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36398865 + 36398866.

It is an arithmetic number, because the mean of its divisors is an integer number (36398866).

Almost surely, 2^72797731 is an apocalyptic number.

72797731 is a deficient number, since it is larger than the sum of its proper divisors (1).

72797731 is an equidigital number, since it uses as much as digits as its factorization.

72797731 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 129654, while the sum is 43.

The square root of 72797731 is about 8532.1586365937. The cubic root of 72797731 is about 417.5475576599.

The spelling of 72797731 in words is "seventy-two million, seven hundred ninety-seven thousand, seven hundred thirty-one".