631312553 has 4 divisors (see below), whose sum is σ = 635549700. Its totient is φ = 627075408.

The previous prime is 631312531. The next prime is 631312559. The reversal of 631312553 is 355213136.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 35366809 + 595945744 = 5947^2 + 24412^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-631312553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (631312559) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2118350 + ... + 2118647.

It is an arithmetic number, because the mean of its divisors is an integer number (158887425).

Almost surely, 2^631312553 is an apocalyptic number.

It is an amenable number.

631312553 is a deficient number, since it is larger than the sum of its proper divisors (4237147).

631312553 is a wasteful number, since it uses less digits than its factorization.

631312553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4237146.

The product of its digits is 8100, while the sum is 29.

The square root of 631312553 is about 25125.9338731917. The cubic root of 631312553 is about 857.8568200540.

Adding to 631312553 its reverse (355213136), we get a palindrome (986525689).

The spelling of 631312553 in words is "six hundred thirty-one million, three hundred twelve thousand, five hundred fifty-three".