166663945 has 24 divisors (see below), whose sum is σ = 235081224. Its totient is φ = 113089536.

The previous prime is 166663933. The next prime is 166663951. The reversal of 166663945 is 549366661.

It can be written as a sum of positive squares in 4 ways, for example, as 36156169 + 130507776 = 6013^2 + 11424^2 .

It is not a de Polignac number, because 166663945 - 2⁷ = 166663817 is a prime.

It is a super-3 number, since 3×166663945³ (a number of 26 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (46) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 166663895 and 166663904.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20259 + ... + 27271.

It is an arithmetic number, because the mean of its divisors is an integer number (9795051).

Almost surely, 2^166663945 is an apocalyptic number.

It is an amenable number.

166663945 is a deficient number, since it is larger than the sum of its proper divisors (68417279).

166663945 is an equidigital number, since it uses as much as digits as its factorization.

166663945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7129 (or 7122 counting only the distinct ones).

The product of its digits is 699840, while the sum is 46.

The square root of 166663945 is about 12909.8390772310. The cubic root of 166663945 is about 550.3182125510.

The spelling of 166663945 in words is "one hundred sixty-six million, six hundred sixty-three thousand, nine hundred forty-five".