631691873 has 2 divisors, whose sum is σ = 631691874. Its totient is φ = 631691872.

The previous prime is 631691779. The next prime is 631691881. The reversal of 631691873 is 378196136.

631691873 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 601573729 + 30118144 = 24527^2 + 5488^2 .

It is a cyclic number.

It is not a de Polignac number, because 631691873 - 2¹⁴ = 631675489 is a prime.

It is not a weakly prime, because it can be changed into another prime (631691273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 315845936 + 315845937.

It is an arithmetic number, because the mean of its divisors is an integer number (315845937).

Almost surely, 2^631691873 is an apocalyptic number.

It is an amenable number.

631691873 is a deficient number, since it is larger than the sum of its proper divisors (1).

631691873 is an equidigital number, since it uses as much as digits as its factorization.

631691873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 163296, while the sum is 44.

The square root of 631691873 is about 25133.4811158343. The cubic root of 631691873 is about 858.0285981995.

It can be divided in two parts, 6316 and 91873, that added together give a palindrome (98189).

The spelling of 631691873 in words is "six hundred thirty-one million, six hundred ninety-one thousand, eight hundred seventy-three".