66312881625 has 32 divisors (see below), whose sum is σ = 112692423168. Its totient is φ = 34614374400.

The previous prime is 66312881561. The next prime is 66312881629. The reversal of 66312881625 is 52618821366.

It is a happy number.

It is not a de Polignac number, because 66312881625 - 2⁶ = 66312881561 is a prime.

It is a super-2 number, since 2×66312881625² (a number of 22 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66312881629) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1863592 + ... + 1898841.

It is an arithmetic number, because the mean of its divisors is an integer number (3521638224).

Almost surely, 2^66312881625 is an apocalyptic number.

It is an amenable number.

66312881625 is a deficient number, since it is larger than the sum of its proper divisors (46379541543).

66312881625 is a wasteful number, since it uses less digits than its factorization.

66312881625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3762498 (or 3762488 counting only the distinct ones).

The product of its digits is 829440, while the sum is 48.

The spelling of 66312881625 in words is "sixty-six billion, three hundred twelve million, eight hundred eighty-one thousand, six hundred twenty-five".