31581503243 has 2 divisors, whose sum is σ = 31581503244. Its totient is φ = 31581503242.

The previous prime is 31581503197. The next prime is 31581503249. The reversal of 31581503243 is 34230518513.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 31581503243 - 2¹⁸ = 31581241099 is a prime.

It is not a weakly prime, because it can be changed into another prime (31581503249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15790751621 + 15790751622.

It is an arithmetic number, because the mean of its divisors is an integer number (15790751622).

Almost surely, 2^31581503243 is an apocalyptic number.

31581503243 is a deficient number, since it is larger than the sum of its proper divisors (1).

31581503243 is an equidigital number, since it uses as much as digits as its factorization.

31581503243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43200, while the sum is 35.

The spelling of 31581503243 in words is "thirty-one billion, five hundred eighty-one million, five hundred three thousand, two hundred forty-three".