631243709 has 2 divisors, whose sum is σ = 631243710. Its totient is φ = 631243708.

The previous prime is 631243703. The next prime is 631243757. The reversal of 631243709 is 907342136.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 481670809 + 149572900 = 21947^2 + 12230^2 .

It is a cyclic number.

It is not a de Polignac number, because 631243709 - 2⁸ = 631243453 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (631243703) 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, 315621854 + 315621855.

It is an arithmetic number, because the mean of its divisors is an integer number (315621855).

Almost surely, 2^631243709 is an apocalyptic number.

It is an amenable number.

631243709 is a deficient number, since it is larger than the sum of its proper divisors (1).

631243709 is an equidigital number, since it uses as much as digits as its factorization.

631243709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27216, while the sum is 35.

The square root of 631243709 is about 25124.5638569110. The cubic root of 631243709 is about 857.8256361121.

The spelling of 631243709 in words is "six hundred thirty-one million, two hundred forty-three thousand, seven hundred nine".