721120 has 24 divisors (see below), whose sum is σ = 1704024. Its totient is φ = 288384.

The previous prime is 721117. The next prime is 721129. The reversal of 721120 is 21127.

It is a self number, because there is not a number n which added to its sum of digits gives 721120.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721129) 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, 2094 + ... + 2413.

It is an arithmetic number, because the mean of its divisors is an integer number (71001).

2⁷²¹¹²⁰ is an apocalyptic number.

It is an amenable number.

721120 is an abundant number, since it is smaller than the sum of its proper divisors (982904).

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

721120 is a wasteful number, since it uses less digits than its factorization.

721120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4522 (or 4514 counting only the distinct ones).

The product of its (nonzero) digits is 28, while the sum is 13.

The square root of 721120 is about 849.1878472988. The cubic root of 721120 is about 89.6745446814.

Adding to 721120 its reverse (21127), we get a palindrome (742247).

It can be divided in two parts, 721 and 120, that added together give a square (841 = 29²).

The spelling of 721120 in words is "seven hundred twenty-one thousand, one hundred twenty", and thus it is an iban number.