661197496320 has 448 divisors, whose sum is σ = 2357233223040. Its totient is φ = 175835971584.

The previous prime is 661197496231. The next prime is 661197496357. The reversal of 661197496320 is 23694791166.

661197496320 is a `hidden beast` number, since 6 + 6 + 119 + 7 + 496 + 32 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 604937694 + ... + 604938786.

Almost surely, 2^661197496320 is an apocalyptic number.

661197496320 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 661197496320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1178616611520).

661197496320 is an abundant number, since it is smaller than the sum of its proper divisors (1696035726720).

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

661197496320 is a wasteful number, since it uses less digits than its factorization.

661197496320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1680 (or 1650 counting only the distinct ones).

The product of its (nonzero) digits is 2939328, while the sum is 54.

The spelling of 661197496320 in words is "six hundred sixty-one billion, one hundred ninety-seven million, four hundred ninety-six thousand, three hundred twenty".