66172718042 has 8 divisors (see below), whose sum is σ = 105097846356. Its totient is φ = 31140102592.

The previous prime is 66172718041. The next prime is 66172718069. The reversal of 66172718042 is 24081727166.

It can be written as a sum of positive squares in 2 ways, for example, as 65238865561 + 933852481 = 255419^2 + 30559^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×66172718042² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 66172717984 and 66172718002.

It is not an unprimeable number, because it can be changed into a prime (66172718041) 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, 973128173 + ... + 973128240.

Almost surely, 2^66172718042 is an apocalyptic number.

66172718042 is a deficient number, since it is larger than the sum of its proper divisors (38925128314).

66172718042 is a wasteful number, since it uses less digits than its factorization.

66172718042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1946256432.

The product of its (nonzero) digits is 225792, while the sum is 44.

The spelling of 66172718042 in words is "sixty-six billion, one hundred seventy-two million, seven hundred eighteen thousand, forty-two".