66623714355172 has 12 divisors (see below), whose sum is σ = 125560077054076. Its totient is φ = 30749406625440.

The previous prime is 66623714355157. The next prime is 66623714355173. The reversal of 66623714355172 is 27155341732666.

It can be written as a sum of positive squares in 2 ways, for example, as 31635945173056 + 34987769182116 = 5624584^2 + 5915046^2 .

It is not an unprimeable number, because it can be changed into a prime (66623714355173) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 640612637979 + ... + 640612638082.

Almost surely, 2^{66623714355172} is an apocalyptic number.

It is an amenable number.

66623714355172 is a deficient number, since it is larger than the sum of its proper divisors (58936362698904).

66623714355172 is a wasteful number, since it uses less digits than its factorization.

66623714355172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1281225276078 (or 1281225276076 counting only the distinct ones).

The product of its digits is 38102400, while the sum is 58.

The spelling of 66623714355172 in words is "sixty-six trillion, six hundred twenty-three billion, seven hundred fourteen million, three hundred fifty-five thousand, one hundred seventy-two".