721385312 has 24 divisors (see below), whose sum is σ = 1494977400. Its totient is φ = 341708544.

The previous prime is 721385309. The next prime is 721385321. The reversal of 721385312 is 213583127.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 592637 + ... + 593852.

It is an arithmetic number, because the mean of its divisors is an integer number (62290725).

Almost surely, 2^721385312 is an apocalyptic number.

It is an amenable number.

721385312 is an abundant number, since it is smaller than the sum of its proper divisors (773592088).

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

721385312 is a wasteful number, since it uses less digits than its factorization.

721385312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1186518 (or 1186510 counting only the distinct ones).

The product of its digits is 10080, while the sum is 32.

The square root of 721385312 is about 26858.6170902375. The cubic root of 721385312 is about 896.8554091671.

The spelling of 721385312 in words is "seven hundred twenty-one million, three hundred eighty-five thousand, three hundred twelve".