631288989 has 12 divisors (see below), whose sum is σ = 929067516. Its totient is φ = 412918272.

The previous prime is 631288969. The next prime is 631288997. The reversal of 631288989 is 989882136.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 283652964 + 347636025 = 16842^2 + 18645^2 .

It is not a de Polignac number, because 631288989 - 2¹¹ = 631286941 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631288909) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 661252 + ... + 662205.

It is an arithmetic number, because the mean of its divisors is an integer number (77422293).

Almost surely, 2^631288989 is an apocalyptic number.

It is an amenable number.

631288989 is a deficient number, since it is larger than the sum of its proper divisors (297778527).

631288989 is a wasteful number, since it uses less digits than its factorization.

631288989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1323516 (or 1323513 counting only the distinct ones).

The product of its digits is 1492992, while the sum is 54.

The square root of 631288989 is about 25125.4649509218. The cubic root of 631288989 is about 857.8461466353.

The spelling of 631288989 in words is "six hundred thirty-one million, two hundred eighty-eight thousand, nine hundred eighty-nine".