666823127957 has 16 divisors (see below), whose sum is σ = 802258972800. Its totient is φ = 541436063040.

The previous prime is 666823127941. The next prime is 666823127963. The reversal of 666823127957 is 759721328666.

It is a cyclic number.

It is not a de Polignac number, because 666823127957 - 2⁴ = 666823127941 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 666823127957.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666823127917) 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, 1475207 + ... + 1873467.

It is an arithmetic number, because the mean of its divisors is an integer number (50141185800).

Almost surely, 2^666823127957 is an apocalyptic number.

It is an amenable number.

666823127957 is a deficient number, since it is larger than the sum of its proper divisors (135435844843).

666823127957 is a wasteful number, since it uses less digits than its factorization.

666823127957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 410876.

The product of its digits is 45722880, while the sum is 62.

The spelling of 666823127957 in words is "six hundred sixty-six billion, eight hundred twenty-three million, one hundred twenty-seven thousand, nine hundred fifty-seven".