721415816 has 32 divisors (see below), whose sum is σ = 1509948000. Its totient is φ = 320288640.

The previous prime is 721415797. The next prime is 721415819. The reversal of 721415816 is 618514127.

It is not an unprimeable number, because it can be changed into a prime (721415819) 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, 91541 + ... + 99108.

It is an arithmetic number, because the mean of its divisors is an integer number (47185875).

Almost surely, 2^721415816 is an apocalyptic number.

It is an amenable number.

721415816 is an abundant number, since it is smaller than the sum of its proper divisors (788532184).

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

721415816 is a wasteful number, since it uses less digits than its factorization.

721415816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190709 (or 190705 counting only the distinct ones).

The product of its digits is 13440, while the sum is 35.

The square root of 721415816 is about 26859.1849466807. The cubic root of 721415816 is about 896.8680502580.

The spelling of 721415816 in words is "seven hundred twenty-one million, four hundred fifteen thousand, eight hundred sixteen".