81597167 has 2 divisors, whose sum is σ = 81597168. Its totient is φ = 81597166.

The previous prime is 81597151. The next prime is 81597179. The reversal of 81597167 is 76179518.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81597167 - 2⁴ = 81597151 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81597067) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40798583 + 40798584.

It is an arithmetic number, because the mean of its divisors is an integer number (40798584).

Almost surely, 2^81597167 is an apocalyptic number.

81597167 is a deficient number, since it is larger than the sum of its proper divisors (1).

81597167 is an equidigital number, since it uses as much as digits as its factorization.

81597167 is an evil number, because the sum of its binary digits is even.

The product of its digits is 105840, while the sum is 44.

The square root of 81597167 is about 9033.1150219622. The cubic root of 81597167 is about 433.7355574370.

The spelling of 81597167 in words is "eighty-one million, five hundred ninety-seven thousand, one hundred sixty-seven".