66167722556 has 12 divisors (see below), whose sum is σ = 124700707992. Its totient is φ = 30538948848.

The previous prime is 66167722529. The next prime is 66167722619. The reversal of 66167722556 is 65522776166.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 66167722498 and 66167722507.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 636228050 + ... + 636228153.

It is an arithmetic number, because the mean of its divisors is an integer number (10391725666).

Almost surely, 2^66167722556 is an apocalyptic number.

It is an amenable number.

66167722556 is a deficient number, since it is larger than the sum of its proper divisors (58532985436).

66167722556 is a wasteful number, since it uses less digits than its factorization.

66167722556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1272456220 (or 1272456218 counting only the distinct ones).

The product of its digits is 6350400, while the sum is 53.

The spelling of 66167722556 in words is "sixty-six billion, one hundred sixty-seven million, seven hundred twenty-two thousand, five hundred fifty-six".