66405072374784 has 2112 divisors, whose sum is σ = 243595897896960. Its totient is φ = 17692286976000.

The previous prime is 66405072374749. The next prime is 66405072374791. The reversal of 66405072374784 is 48747327050466.

66405072374784 is a `hidden beast` number, since 6 + 6 + 4 + 0 + 507 + 2 + 3 + 7 + 47 + 84 = 666.

It is a tau number, because it is divible by the number of its divisors (2112).

It is a super-2 number, since 2×66405072374784² (a number of 28 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 113126187739 + ... + 113126188325.

Almost surely, 2^{66405072374784} is an apocalyptic number.

66405072374784 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 66405072374784, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (121797948948480).

66405072374784 is an abundant number, since it is smaller than the sum of its proper divisors (177190825522176).

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

66405072374784 is a wasteful number, since it uses less digits than its factorization.

66405072374784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 755 (or 718 counting only the distinct ones).

The product of its (nonzero) digits is 189665280, while the sum is 63.

The spelling of 66405072374784 in words is "sixty-six trillion, four hundred five billion, seventy-two million, three hundred seventy-four thousand, seven hundred eighty-four".