666616431 has 16 divisors (see below), whose sum is σ = 959101920. Its totient is φ = 409407360.

The previous prime is 666616411. The next prime is 666616441. The reversal of 666616431 is 134616666.

It is not a de Polignac number, because 666616431 - 2⁶ = 666616367 is a prime.

It is a super-2 number, since 2×666616431² = 888754932158355522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a self number, because there is not a number n which added to its sum of digits gives 666616431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666616411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3061 + ... + 36641.

It is an arithmetic number, because the mean of its divisors is an integer number (59943870).

Almost surely, 2^666616431 is an apocalyptic number.

666616431 is a deficient number, since it is larger than the sum of its proper divisors (292485489).

666616431 is a wasteful number, since it uses less digits than its factorization.

666616431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34106.

The product of its digits is 93312, while the sum is 39.

The square root of 666616431 is about 25818.9161468873. The cubic root of 666616431 is about 873.5585217366.

The spelling of 666616431 in words is "six hundred sixty-six million, six hundred sixteen thousand, four hundred thirty-one".