666126313120720 has 40 divisors (see below), whose sum is σ = 1548750472159176. Its totient is φ = 266449356361728.

The previous prime is 666126313120711. The next prime is 666126313120729. The reversal of 666126313120720 is 27021313621666.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (666126313120711) and next prime (666126313120729).

It can be written as a sum of positive squares in 4 ways, for example, as 4481570448784 + 661644742671936 = 2116972^2 + 25722456^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666126313120729) 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, 202284 + ... + 36500596.

Almost surely, 2^{666126313120720} is an apocalyptic number.

It is an amenable number.

666126313120720 is an abundant number, since it is smaller than the sum of its proper divisors (882624159038456).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

666126313120720 is a wasteful number, since it uses less digits than its factorization.

666126313120720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36527719 (or 36527713 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 46.

The spelling of 666126313120720 in words is "six hundred sixty-six trillion, one hundred twenty-six billion, three hundred thirteen million, one hundred twenty thousand, seven hundred twenty".