721125 has 24 divisors (see below), whose sum is σ = 1301976. Its totient is φ = 384000.

The previous prime is 721117. The next prime is 721129. The reversal of 721125 is 521127.

It can be written as a sum of positive squares in 4 ways, for example, as 324 + 720801 = 18^2 + 849^2 .

It is not a de Polignac number, because 721125 - 2³ = 721117 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 721098 and 721107.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 721125.

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 23 ways as a sum of consecutive naturals, for example, 805 + ... + 1445.

It is an arithmetic number, because the mean of its divisors is an integer number (54249).

2⁷²¹¹²⁵ is an apocalyptic number.

721125 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

It is an amenable number.

721125 is a deficient number, since it is larger than the sum of its proper divisors (580851).

721125 is a wasteful number, since it uses less digits than its factorization.

721125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 662 (or 649 counting only the distinct ones).

The product of its digits is 140, while the sum is 18.

The square root of 721125 is about 849.1907912831. The cubic root of 721125 is about 89.6747519385.

The spelling of 721125 in words is "seven hundred twenty-one thousand, one hundred twenty-five".