66496555125 has 416 divisors, whose sum is σ = 167135963904. Its totient is φ = 25509168000.

The previous prime is 66496555117. The next prime is 66496555127. The reversal of 66496555125 is 52155569466.

It is a happy number.

66496555125 is a `hidden beast` number, since 6 + 6 + 4 + 9 + 65 + 551 + 25 = 666.

It is not a de Polignac number, because 66496555125 - 2³ = 66496555117 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66496555127) by changing a digit.

It is a polite number, since it can be written in 415 ways as a sum of consecutive naturals, for example, 5115119619 + ... + 5115119631.

It is an arithmetic number, because the mean of its divisors is an integer number (401769144).

Almost surely, 2^66496555125 is an apocalyptic number.

66496555125 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

66496555125 is an abundant number, since it is smaller than the sum of its proper divisors (100639408779).

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

66496555125 is an frugal number, since it uses more digits than its factorization.

66496555125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82 (or 39 counting only the distinct ones).

The product of its digits is 9720000, while the sum is 54.

The spelling of 66496555125 in words is "sixty-six billion, four hundred ninety-six million, five hundred fifty-five thousand, one hundred twenty-five".