166657551 has 16 divisors (see below), whose sum is σ = 231116160. Its totient is φ = 106737120.

The previous prime is 166657549. The next prime is 166657553. The reversal of 166657551 is 155756661.

It is an interprime number because it is at equal distance from previous prime (166657549) and next prime (166657553).

It is not a de Polignac number, because 166657551 - 2¹ = 166657549 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166657553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2721 + ... + 18458.

It is an arithmetic number, because the mean of its divisors is an integer number (14444760).

Almost surely, 2^166657551 is an apocalyptic number.

166657551 is a deficient number, since it is larger than the sum of its proper divisors (64458609).

166657551 is a wasteful number, since it uses less digits than its factorization.

166657551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21286.

The product of its digits is 189000, while the sum is 42.

The square root of 166657551 is about 12909.5914342786. The cubic root of 166657551 is about 550.3111748768.

The spelling of 166657551 in words is "one hundred sixty-six million, six hundred fifty-seven thousand, five hundred fifty-one".