61320720384 has 832 divisors, whose sum is σ = 239046144000. Its totient is φ = 15049359360.

The previous prime is 61320720361. The next prime is 61320720421. The reversal of 61320720384 is 48302702316.

It is a happy number.

61320720384 is a `hidden beast` number, since 613 + 2 + 0 + 7 + 2 + 0 + 38 + 4 = 666.

61320720384 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 161795907 + ... + 161796285.

Almost surely, 2^61320720384 is an apocalyptic number.

61320720384 is a gapful number since it is divisible by the number (64) 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 61320720384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (119523072000).

61320720384 is an abundant number, since it is smaller than the sum of its proper divisors (177725423616).

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

61320720384 is a wasteful number, since it uses less digits than its factorization.

61320720384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 449 (or 421 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The spelling of 61320720384 in words is "sixty-one billion, three hundred twenty million, seven hundred twenty thousand, three hundred eighty-four".