666616131 has 6 divisors (see below), whose sum is σ = 962889980. Its totient is φ = 444410748.

The previous prime is 666616123. The next prime is 666616133. The reversal of 666616131 is 131616666.

It is a happy number.

It is not a de Polignac number, because 666616131 - 2³ = 666616123 is a prime.

It is a super-2 number, since 2×666616131² = 888754132218818322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666616133) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 37034221 + ... + 37034238.

Almost surely, 2^666616131 is an apocalyptic number.

666616131 is a deficient number, since it is larger than the sum of its proper divisors (296273849).

666616131 is a wasteful number, since it uses less digits than its factorization.

666616131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74068465 (or 74068462 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 666616131 is about 25818.9103371928. The cubic root of 666616131 is about 873.5583906929.

The spelling of 666616131 in words is "six hundred sixty-six million, six hundred sixteen thousand, one hundred thirty-one".