664392169980 has 432 divisors, whose sum is σ = 2535042095040. Its totient is φ = 137870346240.

The previous prime is 664392169949. The next prime is 664392170017. The reversal of 664392169980 is 89961293466.

664392169980 is a `hidden beast` number, since 6 + 6 + 4 + 392 + 169 + 9 + 80 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 133704936 + ... + 133709904.

Almost surely, 2^664392169980 is an apocalyptic number.

664392169980 is a gapful number since it is divisible by the number (60) 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 664392169980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1267521047520).

664392169980 is an abundant number, since it is smaller than the sum of its proper divisors (1870649925060).

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

664392169980 is a wasteful number, since it uses less digits than its factorization.

664392169980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5890 (or 5874 counting only the distinct ones).

The product of its (nonzero) digits is 30233088, while the sum is 63.

The spelling of 664392169980 in words is "six hundred sixty-four billion, three hundred ninety-two million, one hundred sixty-nine thousand, nine hundred eighty".