721981984 has 24 divisors (see below), whose sum is σ = 1422102528. Its totient is φ = 360813120.

The previous prime is 721981979. The next prime is 721981987. The reversal of 721981984 is 489189127.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (721981987) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 81249 + ... + 89695.

It is an arithmetic number, because the mean of its divisors is an integer number (59254272).

Almost surely, 2^721981984 is an apocalyptic number.

It is an amenable number.

721981984 is a deficient number, since it is larger than the sum of its proper divisors (700120544).

721981984 is a wasteful number, since it uses less digits than its factorization.

721981984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11128 (or 11120 counting only the distinct ones).

The product of its digits is 290304, while the sum is 49.

The square root of 721981984 is about 26869.7224399509. The cubic root of 721981984 is about 897.1026099492.

The spelling of 721981984 in words is "seven hundred twenty-one million, nine hundred eighty-one thousand, nine hundred eighty-four".