667256172181 has 8 divisors (see below), whose sum is σ = 691814847744. Its totient is φ = 642887139360.

The previous prime is 667256172179. The next prime is 667256172221. The reversal of 667256172181 is 181271652766.

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 667256172181 - 2¹ = 667256172179 is a prime.

It is a super-2 number, since 2×667256172181² (a number of 24 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 (667256172161) 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, 47403520 + ... + 47417593.

It is an arithmetic number, because the mean of its divisors is an integer number (86476855968).

Almost surely, 2^667256172181 is an apocalyptic number.

It is an amenable number.

667256172181 is a deficient number, since it is larger than the sum of its proper divisors (24558675563).

667256172181 is a wasteful number, since it uses less digits than its factorization.

667256172181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94821371.

The product of its digits is 1693440, while the sum is 52.

The spelling of 667256172181 in words is "six hundred sixty-seven billion, two hundred fifty-six million, one hundred seventy-two thousand, one hundred eighty-one".