31540043831 has 2 divisors, whose sum is σ = 31540043832. Its totient is φ = 31540043830.

The previous prime is 31540043809. The next prime is 31540043863. The reversal of 31540043831 is 13834004513.

It is an a-pointer prime, because the next prime (31540043863) can be obtained adding 31540043831 to its sum of digits (32).

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31540043831 is a prime.

It is a super-2 number, since 2×31540043831² (a number of 22 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31540043881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15770021915 + 15770021916.

It is an arithmetic number, because the mean of its divisors is an integer number (15770021916).

Almost surely, 2^31540043831 is an apocalyptic number.

31540043831 is a deficient number, since it is larger than the sum of its proper divisors (1).

31540043831 is an equidigital number, since it uses as much as digits as its factorization.

31540043831 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 32.

The spelling of 31540043831 in words is "thirty-one billion, five hundred forty million, forty-three thousand, eight hundred thirty-one".