166957986 has 128 divisors (see below), whose sum is σ = 405409536. Its totient is φ = 45342720.

The previous prime is 166957979. The next prime is 166958021. The reversal of 166957986 is 689759661.

It is a happy number.

It is a super-3 number, since 3×166957986³ (a number of 26 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2011501 + ... + 2011583.

It is an arithmetic number, because the mean of its divisors is an integer number (3167262).

Almost surely, 2^166957986 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 166957986, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (202704768).

166957986 is an abundant number, since it is smaller than the sum of its proper divisors (238451550).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166957986 is a wasteful number, since it uses less digits than its factorization.

166957986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196.

The product of its digits is 4898880, while the sum is 57.

The square root of 166957986 is about 12921.2223106020. Note that the first 3 decimals coincide. The cubic root of 166957986 is about 550.6416599289.

The spelling of 166957986 in words is "one hundred sixty-six million, nine hundred fifty-seven thousand, nine hundred eighty-six".