71831661275681 has 2 divisors, whose sum is σ = 71831661275682. Its totient is φ = 71831661275680.

The previous prime is 71831661275629. The next prime is 71831661275771. The reversal of 71831661275681 is 18657216613817.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70066525830625 + 1765135445056 = 8370575^2 + 1328584^2 .

It is a cyclic number.

It is not a de Polignac number, because 71831661275681 - 2⁶ = 71831661275617 is a prime.

It is a super-2 number, since 2×71831661275681² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (71831661215681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35915830637840 + 35915830637841.

It is an arithmetic number, because the mean of its divisors is an integer number (35915830637841).

Almost surely, 2^{71831661275681} is an apocalyptic number.

It is an amenable number.

71831661275681 is a deficient number, since it is larger than the sum of its proper divisors (1).

71831661275681 is an equidigital number, since it uses as much as digits as its factorization.

71831661275681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20321280, while the sum is 62.

The spelling of 71831661275681 in words is "seventy-one trillion, eight hundred thirty-one billion, six hundred sixty-one million, two hundred seventy-five thousand, six hundred eighty-one".