166011557 has 2 divisors, whose sum is σ = 166011558. Its totient is φ = 166011556.

The previous prime is 166011553. The next prime is 166011623. The reversal of 166011557 is 755110661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 86694721 + 79316836 = 9311^2 + 8906^2 .

It is a cyclic number.

It is not a de Polignac number, because 166011557 - 2² = 166011553 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166011553) 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, 83005778 + 83005779.

It is an arithmetic number, because the mean of its divisors is an integer number (83005779).

Almost surely, 2^166011557 is an apocalyptic number.

It is an amenable number.

166011557 is a deficient number, since it is larger than the sum of its proper divisors (1).

166011557 is an equidigital number, since it uses as much as digits as its factorization.

166011557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6300, while the sum is 32.

The square root of 166011557 is about 12884.5472175005. The cubic root of 166011557 is about 549.5992198717.

The spelling of 166011557 in words is "one hundred sixty-six million, eleven thousand, five hundred fifty-seven".