721591960320 has 2016 divisors, whose sum is σ = 3296876373504. Its totient is φ = 148134666240.

The previous prime is 721591960277. The next prime is 721591960361. The reversal of 721591960320 is 23069195127.

It is a happy number.

721591960320 is a `hidden beast` number, since 7 + 2 + 1 + 5 + 9 + 19 + 603 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (2016).

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

It is an unprimeable number.

It is a polite number, since it can be written in 223 ways as a sum of consecutive naturals, for example, 8693878999 + ... + 8693879081.

It is an arithmetic number, because the mean of its divisors is an integer number (1635355344).

Almost surely, 2^721591960320 is an apocalyptic number.

721591960320 is a gapful number since it is divisible by the number (70) 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 721591960320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1648438186752).

721591960320 is an abundant number, since it is smaller than the sum of its proper divisors (2575284413184).

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

721591960320 is an frugal number, since it uses more digits than its factorization.

721591960320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162 (or 111 counting only the distinct ones).

The product of its (nonzero) digits is 204120, while the sum is 45.

The spelling of 721591960320 in words is "seven hundred twenty-one billion, five hundred ninety-one million, nine hundred sixty thousand, three hundred twenty".