723631 has 4 divisors (see below), whose sum is σ = 726472. Its totient is φ = 720792.

The previous prime is 723623. The next prime is 723661. The reversal of 723631 is 136327.

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 723631 - 2³ = 723623 is a prime.

It is a super-2 number, since 2×723631² = 1047283648322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (723601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 996 + ... + 1561.

It is an arithmetic number, because the mean of its divisors is an integer number (181618).

2⁷²³⁶³¹ is an apocalyptic number.

723631 is a deficient number, since it is larger than the sum of its proper divisors (2841).

723631 is a wasteful number, since it uses less digits than its factorization.

723631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2840.

The product of its digits is 756, while the sum is 22.

The square root of 723631 is about 850.6650339587. The cubic root of 723631 is about 89.7785088526.

Adding to 723631 its reverse (136327), we get a palindrome (859958).

The spelling of 723631 in words is "seven hundred twenty-three thousand, six hundred thirty-one".