166601693 has 4 divisors (see below), whose sum is σ = 166673820. Its totient is φ = 166529568.

The previous prime is 166601689. The next prime is 166601707. The reversal of 166601693 is 396106661.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 59644729 + 106956964 = 7723^2 + 10342^2 .

It is a cyclic number.

It is not a de Polignac number, because 166601693 - 2² = 166601689 is a prime.

It is a super-2 number, since 2×166601693² = 55512248220932498, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

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

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32480 + ... + 37257.

It is an arithmetic number, because the mean of its divisors is an integer number (41668455).

Almost surely, 2^166601693 is an apocalyptic number.

It is an amenable number.

166601693 is a deficient number, since it is larger than the sum of its proper divisors (72127).

166601693 is an equidigital number, since it uses as much as digits as its factorization.

166601693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72126.

The product of its (nonzero) digits is 34992, while the sum is 38.

The square root of 166601693 is about 12907.4278227693. The cubic root of 166601693 is about 550.2496860807.

The spelling of 166601693 in words is "one hundred sixty-six million, six hundred one thousand, six hundred ninety-three".