631513387 has 2 divisors, whose sum is σ = 631513388. Its totient is φ = 631513386.

The previous prime is 631513343. The next prime is 631513417. The reversal of 631513387 is 783315136.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-631513387 is a prime.

It is not a weakly prime, because it can be changed into another prime (631513327) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 315756693 + 315756694.

It is an arithmetic number, because the mean of its divisors is an integer number (315756694).

Almost surely, 2^631513387 is an apocalyptic number.

631513387 is a deficient number, since it is larger than the sum of its proper divisors (1).

631513387 is an equidigital number, since it uses as much as digits as its factorization.

631513387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45360, while the sum is 37.

The square root of 631513387 is about 25129.9301033648. The cubic root of 631513387 is about 857.9477779319.

The spelling of 631513387 in words is "six hundred thirty-one million, five hundred thirteen thousand, three hundred eighty-seven".