725631 has 4 divisors (see below), whose sum is σ = 967512. Its totient is φ = 483752.

The previous prime is 725603. The next prime is 725639. The reversal of 725631 is 136527.

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

It is a cyclic number.

It is not a de Polignac number, because 725631 - 2⁹ = 725119 is a prime.

It is a super-2 number, since 2×725631² = 1053080696322, which contains 22 as substring.

It is a D-number.

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 725631.

It is not an unprimeable number, because it can be changed into a prime (725639) 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, 120936 + ... + 120941.

It is an arithmetic number, because the mean of its divisors is an integer number (241878).

2⁷²⁵⁶³¹ is an apocalyptic number.

725631 is a deficient number, since it is larger than the sum of its proper divisors (241881).

725631 is a wasteful number, since it uses less digits than its factorization.

725631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241880.

The product of its digits is 1260, while the sum is 24.

The square root of 725631 is about 851.8397736664. The cubic root of 725631 is about 89.8611439014.

The spelling of 725631 in words is "seven hundred twenty-five thousand, six hundred thirty-one".