31427122081 has 2 divisors, whose sum is σ = 31427122082. Its totient is φ = 31427122080.

The previous prime is 31427122079. The next prime is 31427122109. The reversal of 31427122081 is 18022172413.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21343749025 + 10083373056 = 146095^2 + 100416^2 .

It is a cyclic number.

It is not a de Polignac number, because 31427122081 - 2¹ = 31427122079 is a prime.

It is a super-2 number, since 2×31427122081² (a number of 22 digits) contains 22 as substring.

Together with 31427122079, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31427122031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15713561040 + 15713561041.

It is an arithmetic number, because the mean of its divisors is an integer number (15713561041).

Almost surely, 2^31427122081 is an apocalyptic number.

It is an amenable number.

31427122081 is a deficient number, since it is larger than the sum of its proper divisors (1).

31427122081 is an equidigital number, since it uses as much as digits as its factorization.

31427122081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5376, while the sum is 31.

Adding to 31427122081 its reverse (18022172413), we get a palindrome (49449294494).

The spelling of 31427122081 in words is "thirty-one billion, four hundred twenty-seven million, one hundred twenty-two thousand, eighty-one".