31661239668 has 24 divisors (see below), whose sum is σ = 73885368480. Its totient is φ = 10552440480.

The previous prime is 31661239639. The next prime is 31661239669. The reversal of 31661239668 is 86693216613.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 31661239668.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31661239669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59623 + ... + 258606.

It is an arithmetic number, because the mean of its divisors is an integer number (3078557020).

Almost surely, 2^31661239668 is an apocalyptic number.

It is an amenable number.

31661239668 is an abundant number, since it is smaller than the sum of its proper divisors (42224128812).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31661239668 is a wasteful number, since it uses less digits than its factorization.

31661239668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 326527 (or 326525 counting only the distinct ones).

The product of its digits is 1679616, while the sum is 51.

The spelling of 31661239668 in words is "thirty-one billion, six hundred sixty-one million, two hundred thirty-nine thousand, six hundred sixty-eight".