725781 has 32 divisors (see below), whose sum is σ = 1244160. Its totient is φ = 366336.

The previous prime is 725749. The next prime is 725789. The reversal of 725781 is 187527.

It is a happy number.

It is not a de Polignac number, because 725781 - 2⁵ = 725749 is a prime.

It is a super-2 number, since 2×725781² = 1053516119922, which contains 22 as substring.

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 725781.

It is not an unprimeable number, because it can be changed into a prime (725789) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6730 + ... + 6836.

It is an arithmetic number, because the mean of its divisors is an integer number (38880).

2⁷²⁵⁷⁸¹ is an apocalyptic number.

It is an amenable number.

725781 is a deficient number, since it is larger than the sum of its proper divisors (518379).

725781 is a wasteful number, since it uses less digits than its factorization.

725781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153.

The product of its digits is 3920, while the sum is 30.

The square root of 725781 is about 851.9278138434. The cubic root of 725781 is about 89.8673354059.

The spelling of 725781 in words is "seven hundred twenty-five thousand, seven hundred eighty-one".