64197981751680 has 1024 divisors, whose sum is σ = 268482586521600. Its totient is φ = 14194085068800.

The previous prime is 64197981751669. The next prime is 64197981751759. The reversal of 64197981751680 is 8615718979146.

64197981751680 is a `hidden beast` number, since 6 + 4 + 1 + 9 + 7 + 98 + 17 + 516 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a junction number, because it is equal to n+sod(n) for n = 64197981751599 and 64197981751608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 455101960 + ... + 455243000.

It is an arithmetic number, because the mean of its divisors is an integer number (262190025900).

Almost surely, 2^{64197981751680} is an apocalyptic number.

64197981751680 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 64197981751680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (134241293260800).

64197981751680 is an abundant number, since it is smaller than the sum of its proper divisors (204284604769920).

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

64197981751680 is a wasteful number, since it uses less digits than its factorization.

64197981751680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 141200 (or 141182 counting only the distinct ones).

The product of its (nonzero) digits is 182891520, while the sum is 72.

The spelling of 64197981751680 in words is "sixty-four trillion, one hundred ninety-seven billion, nine hundred eighty-one million, seven hundred fifty-one thousand, six hundred eighty".