66727171838 has 8 divisors (see below), whose sum is σ = 100092278880. Its totient is φ = 33363078880.

The previous prime is 66727171837. The next prime is 66727171853. The reversal of 66727171838 is 83817172766.

It is a happy number.

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

It is a super-2 number, since 2×66727171838² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66727171837) 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, 59243 + ... + 370086.

It is an arithmetic number, because the mean of its divisors is an integer number (12511534860).

Almost surely, 2^66727171838 is an apocalyptic number.

66727171838 is a deficient number, since it is larger than the sum of its proper divisors (33365107042).

66727171838 is a wasteful number, since it uses less digits than its factorization.

66727171838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 507042.

The product of its digits is 4741632, while the sum is 56.

The spelling of 66727171838 in words is "sixty-six billion, seven hundred twenty-seven million, one hundred seventy-one thousand, eight hundred thirty-eight".