631709993 has 2 divisors, whose sum is σ = 631709994. Its totient is φ = 631709992.

The previous prime is 631709963. The next prime is 631710031. The reversal of 631709993 is 399907136.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 406949929 + 224760064 = 20173^2 + 14992^2 .

It is a cyclic number.

It is not a de Polignac number, because 631709993 - 2⁸ = 631709737 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (631709963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 315854996 + 315854997.

It is an arithmetic number, because the mean of its divisors is an integer number (315854997).

Almost surely, 2^631709993 is an apocalyptic number.

It is an amenable number.

631709993 is a deficient number, since it is larger than the sum of its proper divisors (1).

631709993 is an equidigital number, since it uses as much as digits as its factorization.

631709993 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 275562, while the sum is 47.

The square root of 631709993 is about 25133.8415885833. The cubic root of 631709993 is about 858.0368022677.

The spelling of 631709993 in words is "six hundred thirty-one million, seven hundred nine thousand, nine hundred ninety-three".