721673964 has 72 divisors (see below), whose sum is σ = 2038654800. Its totient is φ = 213350400.

The previous prime is 721673959. The next prime is 721673971. The reversal of 721673964 is 469376127.

721673964 is a modest number, since divided by 73964 gives 7216 as remainder.

It is an unprimeable number.

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 in 23 ways as a sum of consecutive naturals, for example, 5989 + ... + 38460.

It is an arithmetic number, because the mean of its divisors is an integer number (28314650).

Almost surely, 2^721673964 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 721673964, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1019327400).

721673964 is an abundant number, since it is smaller than the sum of its proper divisors (1316980836).

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

721673964 is a wasteful number, since it uses less digits than its factorization.

721673964 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44511 (or 44506 counting only the distinct ones).

The product of its digits is 381024, while the sum is 45.

The square root of 721673964 is about 26863.9900982710. The cubic root of 721673964 is about 896.9750144978.

The spelling of 721673964 in words is "seven hundred twenty-one million, six hundred seventy-three thousand, nine hundred sixty-four".