721792 has 16 divisors (see below), whose sum is σ = 1438200. Its totient is φ = 360832.

The previous prime is 721783. The next prime is 721793. The reversal of 721792 is 297127.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (16).

It is a self number, because there is not a number n which added to its sum of digits gives 721792.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721793) by changing a digit.

721792 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2692 + ... + 2947.

2⁷²¹⁷⁹² is an apocalyptic number.

It is an amenable number.

721792 is a deficient number, since it is larger than the sum of its proper divisors (716408).

721792 is an equidigital number, since it uses as much as digits as its factorization.

721792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5653 (or 5641 counting only the distinct ones).

The product of its digits is 1764, while the sum is 28.

The square root of 721792 is about 849.5834273337. The cubic root of 721792 is about 89.7023914498.

The spelling of 721792 in words is "seven hundred twenty-one thousand, seven hundred ninety-two".