166313551 has 4 divisors (see below), whose sum is σ = 170181352. Its totient is φ = 162445752.

The previous prime is 166313531. The next prime is 166313561. The reversal of 166313551 is 155313661.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 166313551 - 2⁵ = 166313519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166313501) 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, 1933836 + ... + 1933921.

It is an arithmetic number, because the mean of its divisors is an integer number (42545338).

Almost surely, 2^166313551 is an apocalyptic number.

166313551 is a deficient number, since it is larger than the sum of its proper divisors (3867801).

166313551 is an equidigital number, since it uses as much as digits as its factorization.

166313551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3867800.

The product of its digits is 8100, while the sum is 31.

The square root of 166313551 is about 12896.2611248377. The cubic root of 166313551 is about 549.9322792653.

The spelling of 166313551 in words is "one hundred sixty-six million, three hundred thirteen thousand, five hundred fifty-one".