31523041512581 has 2 divisors, whose sum is σ = 31523041512582. Its totient is φ = 31523041512580.

The previous prime is 31523041512577. The next prime is 31523041512583. The reversal of 31523041512581 is 18521514032513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23053835676481 + 8469205836100 = 4801441^2 + 2910190^2 .

It is a cyclic number.

It is not a de Polignac number, because 31523041512581 - 2² = 31523041512577 is a prime.

It is a super-2 number, since 2×31523041512581² (a number of 28 digits) contains 22 as substring.

Together with 31523041512583, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31523041512583) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15761520756290 + 15761520756291.

It is an arithmetic number, because the mean of its divisors is an integer number (15761520756291).

Almost surely, 2^{31523041512581} is an apocalyptic number.

It is an amenable number.

31523041512581 is a deficient number, since it is larger than the sum of its proper divisors (1).

31523041512581 is an equidigital number, since it uses as much as digits as its factorization.

31523041512581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144000, while the sum is 41.

The spelling of 31523041512581 in words is "thirty-one trillion, five hundred twenty-three billion, forty-one million, five hundred twelve thousand, five hundred eighty-one".