82157731 has 2 divisors, whose sum is σ = 82157732. Its totient is φ = 82157730.

The previous prime is 82157717. The next prime is 82157737. The reversal of 82157731 is 13775128.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 82157731 - 2¹⁵ = 82124963 is a prime.

It is a super-2 number, since 2×82157731² = 13499785526136722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (82157737) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41078865 + 41078866.

It is an arithmetic number, because the mean of its divisors is an integer number (41078866).

Almost surely, 2^82157731 is an apocalyptic number.

82157731 is a deficient number, since it is larger than the sum of its proper divisors (1).

82157731 is an equidigital number, since it uses as much as digits as its factorization.

82157731 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11760, while the sum is 34.

The square root of 82157731 is about 9064.0901915195. The cubic root of 82157731 is about 434.7265308946.

The spelling of 82157731 in words is "eighty-two million, one hundred fifty-seven thousand, seven hundred thirty-one".