166557313 has 16 divisors (see below), whose sum is σ = 195063120. Its totient is φ = 140783616.

The previous prime is 166557301. The next prime is 166557317. The reversal of 166557313 is 313755661.

It can be written as a sum of positive squares in 8 ways, for example, as 13490929 + 153066384 = 3673^2 + 12372^2 .

It is a cyclic number.

It is not a de Polignac number, because 166557313 - 2²¹ = 164460161 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166557317) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2008 + ... + 18361.

It is an arithmetic number, because the mean of its divisors is an integer number (12191445).

Almost surely, 2^166557313 is an apocalyptic number.

166557313 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

166557313 is a deficient number, since it is larger than the sum of its proper divisors (28505807).

166557313 is a wasteful number, since it uses less digits than its factorization.

166557313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20436.

The product of its digits is 56700, while the sum is 37.

The square root of 166557313 is about 12905.7085431215. The cubic root of 166557313 is about 550.2008225321.

The spelling of 166557313 in words is "one hundred sixty-six million, five hundred fifty-seven thousand, three hundred thirteen".