717589505981 has 2 divisors, whose sum is σ = 717589505982. Its totient is φ = 717589505980.

The previous prime is 717589505959. The next prime is 717589506019. The reversal of 717589505981 is 189505985717.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 549464905081 + 168124600900 = 741259^2 + 410030^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-717589505981 is a prime.

It is a super-2 number, since 2×717589505981² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (717580505981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 358794752990 + 358794752991.

It is an arithmetic number, because the mean of its divisors is an integer number (358794752991).

Almost surely, 2^717589505981 is an apocalyptic number.

It is an amenable number.

717589505981 is a deficient number, since it is larger than the sum of its proper divisors (1).

717589505981 is an equidigital number, since it uses as much as digits as its factorization.

717589505981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31752000, while the sum is 65.

The spelling of 717589505981 in words is "seven hundred seventeen billion, five hundred eighty-nine million, five hundred five thousand, nine hundred eighty-one".