631729 has 4 divisors (see below), whose sum is σ = 721984. Its totient is φ = 541476.

The previous prime is 631723. The next prime is 631733. The reversal of 631729 is 927136.

631729 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 631729 - 2¹³ = 623537 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 631697 and 631706.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631723) 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, 45117 + ... + 45130.

It is an arithmetic number, because the mean of its divisors is an integer number (180496).

2⁶³¹⁷²⁹ is an apocalyptic number.

It is an amenable number.

631729 is a deficient number, since it is larger than the sum of its proper divisors (90255).

631729 is an equidigital number, since it uses as much as digits as its factorization.

631729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90254.

The product of its digits is 2268, while the sum is 28.

The square root of 631729 is about 794.8138146761. The cubic root of 631729 is about 85.8045407768.

The spelling of 631729 in words is "six hundred thirty-one thousand, seven hundred twenty-nine".