66172320127 has 8 divisors (see below), whose sum is σ = 66974682096. Its totient is φ = 65370079872.

The previous prime is 66172320077. The next prime is 66172320173. The reversal of 66172320127 is 72102327166.

It is a happy number.

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 66172320127 - 2²⁷ = 66038102399 is a prime.

It is a super-2 number, since 2×66172320127² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66172320827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1569223 + ... + 1610839.

It is an arithmetic number, because the mean of its divisors is an integer number (8371835262).

Almost surely, 2^66172320127 is an apocalyptic number.

66172320127 is a deficient number, since it is larger than the sum of its proper divisors (802361969).

66172320127 is a wasteful number, since it uses less digits than its factorization.

66172320127 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60857.

The product of its (nonzero) digits is 42336, while the sum is 37.

The spelling of 66172320127 in words is "sixty-six billion, one hundred seventy-two million, three hundred twenty thousand, one hundred twenty-seven".