167165561 has 4 divisors (see below), whose sum is σ = 168699300. Its totient is φ = 165631824.

The previous prime is 167165549. The next prime is 167165567. The reversal of 167165561 is 165561761.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 165561761 = 349 ⋅474389.

It can be written as a sum of positive squares in 2 ways, for example, as 86955625 + 80209936 = 9325^2 + 8956^2 .

It is a cyclic number.

It is not a de Polignac number, because 167165561 - 2¹⁸ = 166903417 is a prime.

It is not an unprimeable number, because it can be changed into a prime (167165567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 766706 + ... + 766923.

It is an arithmetic number, because the mean of its divisors is an integer number (42174825).

Almost surely, 2^167165561 is an apocalyptic number.

It is an amenable number.

167165561 is a deficient number, since it is larger than the sum of its proper divisors (1533739).

167165561 is a wasteful number, since it uses less digits than its factorization.

167165561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1533738.

The product of its digits is 37800, while the sum is 38.

The square root of 167165561 is about 12929.2521438790. The cubic root of 167165561 is about 550.8697654329.

The spelling of 167165561 in words is "one hundred sixty-seven million, one hundred sixty-five thousand, five hundred sixty-one".