631023881 has 4 divisors (see below), whose sum is σ = 633732372. Its totient is φ = 628315392.

The previous prime is 631023829. The next prime is 631023893. The reversal of 631023881 is 188320136.

It is a happy number.

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 413756281 + 217267600 = 20341^2 + 14740^2 .

It is a cyclic number.

It is not a de Polignac number, because 631023881 - 2¹⁴ = 631007497 is a prime.

It is a super-2 number, since 2×631023881² = 796382276784604322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (631020881) 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 in 3 ways as a sum of consecutive naturals, for example, 1353896 + ... + 1354361.

It is an arithmetic number, because the mean of its divisors is an integer number (158433093).

Almost surely, 2^631023881 is an apocalyptic number.

It is an amenable number.

631023881 is a deficient number, since it is larger than the sum of its proper divisors (2708491).

631023881 is a wasteful number, since it uses less digits than its factorization.

631023881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2708490.

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 631023881 is about 25120.1887134631. The cubic root of 631023881 is about 857.7260464790.

The spelling of 631023881 in words is "six hundred thirty-one million, twenty-three thousand, eight hundred eighty-one".