166220057 has 4 divisors (see below), whose sum is σ = 173447040. Its totient is φ = 158993076.

The previous prime is 166220023. The next prime is 166220071. The reversal of 166220057 is 750022661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 750022661 = 3847 ⋅194963.

It is a cyclic number.

It is not a de Polignac number, because 166220057 - 2⁶ = 166219993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166220077) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3613457 + ... + 3613502.

It is an arithmetic number, because the mean of its divisors is an integer number (43361760).

Almost surely, 2^166220057 is an apocalyptic number.

It is an amenable number.

166220057 is a deficient number, since it is larger than the sum of its proper divisors (7226983).

166220057 is an equidigital number, since it uses as much as digits as its factorization.

166220057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7226982.

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 166220057 is about 12892.6357662039. The cubic root of 166220057 is about 549.8292108829.

The spelling of 166220057 in words is "one hundred sixty-six million, two hundred twenty thousand, fifty-seven".