631313138821 has 16 divisors (see below), whose sum is σ = 658318212864. Its totient is φ = 604923577024.

The previous prime is 631313138803. The next prime is 631313138873. The reversal of 631313138821 is 128831313136.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 631313138821 - 2⁷ = 631313138693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631313138801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 891951 + ... + 1434643.

It is an arithmetic number, because the mean of its divisors is an integer number (41144888304).

Almost surely, 2^631313138821 is an apocalyptic number.

It is an amenable number.

631313138821 is a deficient number, since it is larger than the sum of its proper divisors (27005074043).

631313138821 is a wasteful number, since it uses less digits than its factorization.

631313138821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 543260.

The product of its digits is 62208, while the sum is 40.

The spelling of 631313138821 in words is "six hundred thirty-one billion, three hundred thirteen million, one hundred thirty-eight thousand, eight hundred twenty-one".