66118478634 has 160 divisors (see below), whose sum is σ = 164575488000. Its totient is φ = 19711133568.

The previous prime is 66118478617. The next prime is 66118478653. The reversal of 66118478634 is 43687481166.

It is a super-4 number, since 4×66118478634⁴ (a number of 44 digits) contains 4444 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

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 79 ways as a sum of consecutive naturals, for example, 11497992 + ... + 11503740.

It is an arithmetic number, because the mean of its divisors is an integer number (1028596800).

Almost surely, 2^66118478634 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66118478634, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82287744000).

66118478634 is an abundant number, since it is smaller than the sum of its proper divisors (98457009366).

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

66118478634 is a wasteful number, since it uses less digits than its factorization.

66118478634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5946 (or 5937 counting only the distinct ones).

The product of its digits is 4644864, while the sum is 54.

The spelling of 66118478634 in words is "sixty-six billion, one hundred eighteen million, four hundred seventy-eight thousand, six hundred thirty-four".