166661650 has 12 divisors (see below), whose sum is σ = 309990762. Its totient is φ = 66664640.

The previous prime is 166661609. The next prime is 166661681. The reversal of 166661650 is 56166661.

166661650 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 137100681 + 29560969 = 11709^2 + 5437^2 .

It is a super-2 number, since 2×166661650² = 55552211161445000, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1666567 + ... + 1666666.

Almost surely, 2^166661650 is an apocalyptic number.

166661650 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

166661650 is a deficient number, since it is larger than the sum of its proper divisors (143329112).

166661650 is a wasteful number, since it uses less digits than its factorization.

166661650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3333245 (or 3333240 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 166661650 is about 12909.7501912314. The cubic root of 166661650 is about 550.3156865376.

It can be divided in two parts, 16 and 6661650, that added together give a palindrome (6661666).

The spelling of 166661650 in words is "one hundred sixty-six million, six hundred sixty-one thousand, six hundred fifty".