31570000081 has 2 divisors, whose sum is σ = 31570000082. Its totient is φ = 31570000080.

The previous prime is 31570000079. The next prime is 31570000103. The reversal of 31570000081 is 18000007513.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19914854400 + 11655145681 = 141120^2 + 107959^2 .

It is a cyclic number.

It is not a de Polignac number, because 31570000081 - 2¹ = 31570000079 is a prime.

It is a super-2 number, since 2×31570000081² (a number of 22 digits) contains 22 as substring.

Together with 31570000079, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31570006081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15785000040 + 15785000041.

It is an arithmetic number, because the mean of its divisors is an integer number (15785000041).

Almost surely, 2^31570000081 is an apocalyptic number.

It is an amenable number.

31570000081 is a deficient number, since it is larger than the sum of its proper divisors (1).

31570000081 is an equidigital number, since it uses as much as digits as its factorization.

31570000081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 840, while the sum is 25.

Adding to 31570000081 its reverse (18000007513), we get a palindrome (49570007594).

The spelling of 31570000081 in words is "thirty-one billion, five hundred seventy million, eighty-one", and thus it is an aban number.