31723127881 has 2 divisors, whose sum is σ = 31723127882. Its totient is φ = 31723127880.

The previous prime is 31723127879. The next prime is 31723127911. The reversal of 31723127881 is 18872132713.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30038435856 + 1684692025 = 173316^2 + 41045^2 .

It is a cyclic number.

It is not a de Polignac number, because 31723127881 - 2¹ = 31723127879 is a prime.

It is a super-2 number, since 2×31723127881² (a number of 22 digits) contains 22 as substring.

Together with 31723127879, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (31723127801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15861563940 + 15861563941.

It is an arithmetic number, because the mean of its divisors is an integer number (15861563941).

Almost surely, 2^31723127881 is an apocalyptic number.

It is an amenable number.

31723127881 is a deficient number, since it is larger than the sum of its proper divisors (1).

31723127881 is an equidigital number, since it uses as much as digits as its factorization.

31723127881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 112896, while the sum is 43.

The spelling of 31723127881 in words is "thirty-one billion, seven hundred twenty-three million, one hundred twenty-seven thousand, eight hundred eighty-one".