66155451264 has 384 divisors, whose sum is σ = 238985510400. Its totient is φ = 17127272448.

The previous prime is 66155451211. The next prime is 66155451289. The reversal of 66155451264 is 46215455166.

66155451264 is a `hidden beast` number, since 6 + 615 + 5 + 4 + 5 + 1 + 26 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3514582 + ... + 3533354.

It is an arithmetic number, because the mean of its divisors is an integer number (622358100).

Almost surely, 2^66155451264 is an apocalyptic number.

66155451264 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66155451264, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119492755200).

66155451264 is an abundant number, since it is smaller than the sum of its proper divisors (172830059136).

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

66155451264 is a wasteful number, since it uses less digits than its factorization.

66155451264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18842 (or 18827 counting only the distinct ones).

The product of its digits is 864000, while the sum is 45.

The spelling of 66155451264 in words is "sixty-six billion, one hundred fifty-five million, four hundred fifty-one thousand, two hundred sixty-four".