31521423432481 has 2 divisors, whose sum is σ = 31521423432482. Its totient is φ = 31521423432480.

The previous prime is 31521423432469. The next prime is 31521423432523. The reversal of 31521423432481 is 18423432412513.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24008863213456 + 7512560219025 = 4899884^2 + 2740905^2 .

It is a cyclic number.

It is not a de Polignac number, because 31521423432481 - 2¹⁹ = 31521422908193 is a prime.

It is a super-2 number, since 2×31521423432481² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (31521423432281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15760711716240 + 15760711716241.

It is an arithmetic number, because the mean of its divisors is an integer number (15760711716241).

Almost surely, 2^{31521423432481} is an apocalyptic number.

It is an amenable number.

31521423432481 is a deficient number, since it is larger than the sum of its proper divisors (1).

31521423432481 is an equidigital number, since it uses as much as digits as its factorization.

31521423432481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 552960, while the sum is 43.

Adding to 31521423432481 its reverse (18423432412513), we get a palindrome (49944855844994).

The spelling of 31521423432481 in words is "thirty-one trillion, five hundred twenty-one billion, four hundred twenty-three million, four hundred thirty-two thousand, four hundred eighty-one".