166727661 has 16 divisors (see below), whose sum is σ = 231075264. Its totient is φ = 106838784.

The previous prime is 166727657. The next prime is 166727677.

166727661 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 166727661 - 2² = 166727657 is a prime.

It is a super-2 number, since 2×166727661² = 55596225885061842, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166725661) 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, 165 + ... + 18261.

It is an arithmetic number, because the mean of its divisors is an integer number (14442204).

Almost surely, 2^166727661 is an apocalyptic number.

It is an amenable number.

166727661 is a deficient number, since it is larger than the sum of its proper divisors (64347603).

166727661 is a wasteful number, since it uses less digits than its factorization.

166727661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18220.

The product of its digits is 127008, while the sum is 42.

The square root of 166727661 is about 12912.3065716393. The cubic root of 166727661 is about 550.3883329117.

The spelling of 166727661 in words is "one hundred sixty-six million, seven hundred twenty-seven thousand, six hundred sixty-one".