31631240661 has 4 divisors (see below), whose sum is σ = 42174987552. Its totient is φ = 21087493772.

The previous prime is 31631240617. The next prime is 31631240699. The reversal of 31631240661 is 16604213613.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 31631240661 - 2¹³ = 31631232469 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31631240461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5271873441 + ... + 5271873446.

It is an arithmetic number, because the mean of its divisors is an integer number (10543746888).

Almost surely, 2^31631240661 is an apocalyptic number.

It is an amenable number.

31631240661 is a deficient number, since it is larger than the sum of its proper divisors (10543746891).

31631240661 is a wasteful number, since it uses less digits than its factorization.

31631240661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10543746890.

The product of its (nonzero) digits is 15552, while the sum is 33.

The spelling of 31631240661 in words is "thirty-one billion, six hundred thirty-one million, two hundred forty thousand, six hundred sixty-one".