31420321210081 has 2 divisors, whose sum is σ = 31420321210082. Its totient is φ = 31420321210080.

The previous prime is 31420321210079. The next prime is 31420321210123. The reversal of 31420321210081 is 18001212302413.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28355720850081 + 3064600360000 = 5325009^2 + 1750600^2 .

It is an emirp because it is prime and its reverse (18001212302413) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31420321210081 - 2¹ = 31420321210079 is a prime.

It is a super-2 number, since 2×31420321210081² (a number of 28 digits) contains 22 as substring.

Together with 31420321210079, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31420321210381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15710160605040 + 15710160605041.

It is an arithmetic number, because the mean of its divisors is an integer number (15710160605041).

Almost surely, 2^{31420321210081} is an apocalyptic number.

It is an amenable number.

31420321210081 is a deficient number, since it is larger than the sum of its proper divisors (1).

31420321210081 is an equidigital number, since it uses as much as digits as its factorization.

31420321210081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 28.

Adding to 31420321210081 its reverse (18001212302413), we get a palindrome (49421533512494).

The spelling of 31420321210081 in words is "thirty-one trillion, four hundred twenty billion, three hundred twenty-one million, two hundred ten thousand, eighty-one".