721329338 has 16 divisors (see below), whose sum is σ = 1140078240. Its totient is φ = 341341200.

The previous prime is 721329337. The next prime is 721329439. The reversal of 721329338 is 833923127.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is not an unprimeable number, because it can be changed into a prime (721329337) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 31373 + ... + 49263.

It is an arithmetic number, because the mean of its divisors is an integer number (71254890).

Almost surely, 2^721329338 is an apocalyptic number.

721329338 is a deficient number, since it is larger than the sum of its proper divisors (418748902).

721329338 is a wasteful number, since it uses less digits than its factorization.

721329338 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18973.

The product of its digits is 54432, while the sum is 38.

The square root of 721329338 is about 26857.5750580725. The cubic root of 721329338 is about 896.8322121866.

The spelling of 721329338 in words is "seven hundred twenty-one million, three hundred twenty-nine thousand, three hundred thirty-eight".