61720888320 has 1056 divisors, whose sum is σ = 270384791040. Its totient is φ = 12669419520.

The previous prime is 61720888267. The next prime is 61720888343. The reversal of 61720888320 is 2388802716.

61720888320 is a `hidden beast` number, since 617 + 2 + 0 + 8 + 8 + 8 + 3 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 171924301 + ... + 171924659.

Almost surely, 2^61720888320 is an apocalyptic number.

61720888320 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 61720888320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (135192395520).

61720888320 is an abundant number, since it is smaller than the sum of its proper divisors (208663902720).

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

61720888320 is a wasteful number, since it uses less digits than its factorization.

61720888320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 451 (or 430 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 45.

The spelling of 61720888320 in words is "sixty-one billion, seven hundred twenty million, eight hundred eighty-eight thousand, three hundred twenty".