725605 has 4 divisors (see below), whose sum is σ = 870732. Its totient is φ = 580480.

The previous prime is 725603. The next prime is 725639. The reversal of 725605 is 506527.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 161604 + 564001 = 402^2 + 751^2 .

It is not a de Polignac number, because 725605 - 2¹ = 725603 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 725605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (725603) 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, 72556 + ... + 72565.

It is an arithmetic number, because the mean of its divisors is an integer number (217683).

2⁷²⁵⁶⁰⁵ is an apocalyptic number.

It is an amenable number.

725605 is a deficient number, since it is larger than the sum of its proper divisors (145127).

725605 is a wasteful number, since it uses less digits than its factorization.

725605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145126.

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 725605 is about 851.8245124437. The cubic root of 725605 is about 89.8600706205.

The spelling of 725605 in words is "seven hundred twenty-five thousand, six hundred five".