165261457 has 2 divisors, whose sum is σ = 165261458. Its totient is φ = 165261456.

The previous prime is 165261389. The next prime is 165261469. The reversal of 165261457 is 754162561.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 88943761 + 76317696 = 9431^2 + 8736^2 .

It is an emirp because it is prime and its reverse (754162561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165261457 - 2²⁷ = 31043729 is a prime.

It is a super-2 number, since 2×165261457² = 54622698339525698, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (165261157) 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, 82630728 + 82630729.

It is an arithmetic number, because the mean of its divisors is an integer number (82630729).

Almost surely, 2^165261457 is an apocalyptic number.

It is an amenable number.

165261457 is a deficient number, since it is larger than the sum of its proper divisors (1).

165261457 is an equidigital number, since it uses as much as digits as its factorization.

165261457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 50400, while the sum is 37.

The square root of 165261457 is about 12855.4057501115. The cubic root of 165261457 is about 548.7702076227.

The spelling of 165261457 in words is "one hundred sixty-five million, two hundred sixty-one thousand, four hundred fifty-seven".