31021343661 has 24 divisors (see below), whose sum is σ = 51958618432. Its totient is φ = 16114982400.

The previous prime is 31021343653. The next prime is 31021343711. The reversal of 31021343661 is 16634312013.

It is not a de Polignac number, because 31021343661 - 2³ = 31021343653 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 (31021344661) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6101620 + ... + 6106701.

Almost surely, 2^31021343661 is an apocalyptic number.

It is an amenable number.

31021343661 is a deficient number, since it is larger than the sum of its proper divisors (20937274771).

31021343661 is a wasteful number, since it uses less digits than its factorization.

31021343661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12208353 (or 12208342 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 30.

Adding to 31021343661 its reverse (16634312013), we get a palindrome (47655655674).

The spelling of 31021343661 in words is "thirty-one billion, twenty-one million, three hundred forty-three thousand, six hundred sixty-one".