66131256558 has 8 divisors (see below), whose sum is σ = 132262513128. Its totient is φ = 22043752184.

The previous prime is 66131256551. The next prime is 66131256601. The reversal of 66131256558 is 85565213166.

It is a happy number.

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

66131256558 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66131256551) 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 3 ways as a sum of consecutive naturals, for example, 5510938041 + ... + 5510938052.

It is an arithmetic number, because the mean of its divisors is an integer number (16532814141).

Almost surely, 2^66131256558 is an apocalyptic number.

66131256558 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66131256558 is a wasteful number, since it uses less digits than its factorization.

66131256558 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11021876098.

The product of its digits is 1296000, while the sum is 48.

The spelling of 66131256558 in words is "sixty-six billion, one hundred thirty-one million, two hundred fifty-six thousand, five hundred fifty-eight".