66171983472 has 240 divisors, whose sum is σ = 231325765632. Its totient is φ = 17220003840.

The previous prime is 66171983467. The next prime is 66171983533. The reversal of 66171983472 is 27438917166.

66171983472 is a `hidden beast` number, since 6 + 617 + 19 + 8 + 3 + 4 + 7 + 2 = 666.

It is a nude number because it is divisible by every one of its digits.

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, 468933 + ... + 593499.

Almost surely, 2^66171983472 is an apocalyptic number.

66171983472 is a gapful number since it is divisible by the number (62) 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 66171983472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (115662882816).

66171983472 is an abundant number, since it is smaller than the sum of its proper divisors (165153782160).

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

66171983472 is a wasteful number, since it uses less digits than its factorization.

66171983472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124636 (or 124627 counting only the distinct ones).

The product of its digits is 3048192, while the sum is 54.

The spelling of 66171983472 in words is "sixty-six billion, one hundred seventy-one million, nine hundred eighty-three thousand, four hundred seventy-two".