166601643 has 16 divisors (see below), whose sum is σ = 239557920. Its totient is φ = 102380544.

The previous prime is 166601623. The next prime is 166601689. The reversal of 166601643 is 346106661.

It is not a de Polignac number, because 166601643 - 2⁶ = 166601579 is a prime.

It is a super-2 number, since 2×166601643² = 55512214900598898, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (166601623) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29755 + ... + 34907.

It is an arithmetic number, because the mean of its divisors is an integer number (14972370).

Almost surely, 2^166601643 is an apocalyptic number.

166601643 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

166601643 is a deficient number, since it is larger than the sum of its proper divisors (72956277).

166601643 is a wasteful number, since it uses less digits than its factorization.

166601643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5998.

The product of its (nonzero) digits is 15552, while the sum is 33.

The square root of 166601643 is about 12907.4258858999. The cubic root of 166601643 is about 550.2496310343.

The spelling of 166601643 in words is "one hundred sixty-six million, six hundred one thousand, six hundred forty-three".