631385 has 8 divisors (see below), whose sum is σ = 762696. Its totient is φ = 501760.

The previous prime is 631361. The next prime is 631387. The reversal of 631385 is 583136.

It can be written as a sum of positive squares in 4 ways, for example, as 373321 + 258064 = 611^2 + 508^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 631385 - 2¹⁶ = 565849 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631387) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 665 + ... + 1305.

It is an arithmetic number, because the mean of its divisors is an integer number (95337).

2⁶³¹³⁸⁵ is an apocalyptic number.

It is an amenable number.

631385 is a deficient number, since it is larger than the sum of its proper divisors (131311).

631385 is a wasteful number, since it uses less digits than its factorization.

631385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 843.

The product of its digits is 2160, while the sum is 26.

The square root of 631385 is about 794.5973823264. The cubic root of 631385 is about 85.7889633582.

The spelling of 631385 in words is "six hundred thirty-one thousand, three hundred eighty-five".