721245384 has 96 divisors (see below), whose sum is σ = 2032386720. Its totient is φ = 239625216.

The previous prime is 721245373. The next prime is 721245397. The reversal of 721245384 is 483542127.

It is a happy number.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1121367 + ... + 1122009.

It is an arithmetic number, because the mean of its divisors is an integer number (21170695).

Almost surely, 2^721245384 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 721245384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1016193360).

721245384 is an abundant number, since it is smaller than the sum of its proper divisors (1311141336).

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

721245384 is a wasteful number, since it uses less digits than its factorization.

721245384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1241 (or 1225 counting only the distinct ones).

The product of its digits is 53760, while the sum is 36.

The square root of 721245384 is about 26856.0120643405. The cubic root of 721245384 is about 896.7974173669.

It can be divided in two parts, 72 and 1245384, that added together give a square (1245456 = 1116²).

The spelling of 721245384 in words is "seven hundred twenty-one million, two hundred forty-five thousand, three hundred eighty-four".