81167057 has 2 divisors, whose sum is σ = 81167058. Its totient is φ = 81167056.

The previous prime is 81167039. The next prime is 81167059. The reversal of 81167057 is 75076118.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75411856 + 5755201 = 8684^2 + 2399^2 .

It is a cyclic number.

It is not a de Polignac number, because 81167057 - 2¹⁸ = 80904913 is a prime.

It is a super-2 number, since 2×81167057² = 13176182284082498, which contains 22 as substring.

Together with 81167059, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (81167059) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40583528 + 40583529.

It is an arithmetic number, because the mean of its divisors is an integer number (40583529).

Almost surely, 2^81167057 is an apocalyptic number.

It is an amenable number.

81167057 is a deficient number, since it is larger than the sum of its proper divisors (1).

81167057 is an equidigital number, since it uses as much as digits as its factorization.

81167057 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11760, while the sum is 35.

The square root of 81167057 is about 9009.2761640434. The cubic root of 81167057 is about 432.9721210140.

The spelling of 81167057 in words is "eighty-one million, one hundred sixty-seven thousand, fifty-seven".