166556513 has 2 divisors, whose sum is σ = 166556514. Its totient is φ = 166556512.

The previous prime is 166556431. The next prime is 166556519. The reversal of 166556513 is 315655661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 85969984 + 80586529 = 9272^2 + 8977^2 .

It is a cyclic number.

It is not a de Polignac number, because 166556513 - 2²² = 162362209 is a prime.

It is not a weakly prime, because it can be changed into another prime (166556519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83278256 + 83278257.

It is an arithmetic number, because the mean of its divisors is an integer number (83278257).

Almost surely, 2^166556513 is an apocalyptic number.

It is an amenable number.

166556513 is a deficient number, since it is larger than the sum of its proper divisors (1).

166556513 is an equidigital number, since it uses as much as digits as its factorization.

166556513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 81000, while the sum is 38.

The square root of 166556513 is about 12905.6775490479. The cubic root of 166556513 is about 550.1999416314.

The spelling of 166556513 in words is "one hundred sixty-six million, five hundred fifty-six thousand, five hundred thirteen".