721020368 has 10 divisors (see below), whose sum is σ = 1396976994. Its totient is φ = 360510176.

The previous prime is 721020367. The next prime is 721020409. The reversal of 721020368 is 863020127.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 696537664 + 24482704 = 26392^2 + 4948^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 721020368.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721020367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22531871 + ... + 22531902.

Almost surely, 2^721020368 is an apocalyptic number.

It is an amenable number.

721020368 is a deficient number, since it is larger than the sum of its proper divisors (675956626).

721020368 is a wasteful number, since it uses less digits than its factorization.

721020368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45063781 (or 45063775 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 721020368 is about 26851.8224334960. The cubic root of 721020368 is about 896.7041459407.

The spelling of 721020368 in words is "seven hundred twenty-one million, twenty thousand, three hundred sixty-eight".