166745986 has 12 divisors (see below), whose sum is σ = 274924566. Its totient is φ = 75793520.

The previous prime is 166745983. The next prime is 166745987. The reversal of 166745986 is 689547661.

It can be written as a sum of positive squares in only one way, i.e., 128119761 + 38626225 = 11319^2 + 6215^2 .

It is a super-2 number, since 2×166745986² = 55608447694224392, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (166745981) 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 in 5 ways as a sum of consecutive naturals, for example, 344275 + ... + 344758.

Almost surely, 2^166745986 is an apocalyptic number.

166745986 is a deficient number, since it is larger than the sum of its proper divisors (108178580).

166745986 is a wasteful number, since it uses less digits than its factorization.

166745986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 689057 (or 689046 counting only the distinct ones).

The product of its digits is 2177280, while the sum is 52.

The square root of 166745986 is about 12913.0161465089. The cubic root of 166745986 is about 550.4084965260.

The spelling of 166745986 in words is "one hundred sixty-six million, seven hundred forty-five thousand, nine hundred eighty-six".