21532631317 has 2 divisors, whose sum is σ = 21532631318. Its totient is φ = 21532631316.

The previous prime is 21532631297. The next prime is 21532631347. The reversal of 21532631317 is 71313623512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20412122641 + 1120508676 = 142871^2 + 33474^2 .

It is a cyclic number.

It is not a de Polignac number, because 21532631317 - 2⁷ = 21532631189 is a prime.

It is a super-3 number, since 3×21532631317³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21532631347) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10766315658 + 10766315659.

It is an arithmetic number, because the mean of its divisors is an integer number (10766315659).

Almost surely, 2^21532631317 is an apocalyptic number.

It is an amenable number.

21532631317 is a deficient number, since it is larger than the sum of its proper divisors (1).

21532631317 is an equidigital number, since it uses as much as digits as its factorization.

21532631317 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22680, while the sum is 34.

The spelling of 21532631317 in words is "twenty-one billion, five hundred thirty-two million, six hundred thirty-one thousand, three hundred seventeen".