666976626445 has 8 divisors (see below), whose sum is σ = 801561215736. Its totient is φ = 532788458496.

The previous prime is 666976626443. The next prime is 666976626517. The reversal of 666976626445 is 544626679666.

It can be written as a sum of positive squares in 4 ways, for example, as 71812208484 + 595164417961 = 267978^2 + 771469^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 666976626445 - 2¹ = 666976626443 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 (666976626443) 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, 99101632 + ... + 99108361.

It is an arithmetic number, because the mean of its divisors is an integer number (100195151967).

Almost surely, 2^666976626445 is an apocalyptic number.

It is an amenable number.

666976626445 is a deficient number, since it is larger than the sum of its proper divisors (134584589291).

666976626445 is a wasteful number, since it uses less digits than its factorization.

666976626445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 198210671.

The product of its digits is 470292480, while the sum is 67.

The spelling of 666976626445 in words is "six hundred sixty-six billion, nine hundred seventy-six million, six hundred twenty-six thousand, four hundred forty-five".