666172479 has 8 divisors (see below), whose sum is σ = 1015120000. Its totient is φ = 380669976.

The previous prime is 666172447. The next prime is 666172511. The reversal of 666172479 is 974271666.

It is an interprime number because it is at equal distance from previous prime (666172447) and next prime (666172511).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 666172479 - 2⁵ = 666172447 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666172439) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15861229 + ... + 15861270.

It is an arithmetic number, because the mean of its divisors is an integer number (126890000).

Almost surely, 2^666172479 is an apocalyptic number.

666172479 is a deficient number, since it is larger than the sum of its proper divisors (348947521).

666172479 is a wasteful number, since it uses less digits than its factorization.

666172479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31722509.

The product of its digits is 762048, while the sum is 48.

The square root of 666172479 is about 25810.3172975460. The cubic root of 666172479 is about 873.3645550318.

It can be divided in two parts, 66617 and 2479, that added together give a palindrome (69096).

The spelling of 666172479 in words is "six hundred sixty-six million, one hundred seventy-two thousand, four hundred seventy-nine".