31603660643 has 2 divisors, whose sum is σ = 31603660644. Its totient is φ = 31603660642.

The previous prime is 31603660633. The next prime is 31603660657. The reversal of 31603660643 is 34606630613.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 31603660643 - 2²⁶ = 31536551779 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31603660597 and 31603660606.

It is not a weakly prime, because it can be changed into another prime (31603660633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15801830321 + 15801830322.

It is an arithmetic number, because the mean of its divisors is an integer number (15801830322).

Almost surely, 2^31603660643 is an apocalyptic number.

31603660643 is a deficient number, since it is larger than the sum of its proper divisors (1).

31603660643 is an equidigital number, since it uses as much as digits as its factorization.

31603660643 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 139968, while the sum is 38.

The spelling of 31603660643 in words is "thirty-one billion, six hundred three million, six hundred sixty thousand, six hundred forty-three".