8539465681 has 2 divisors, whose sum is σ = 8539465682. Its totient is φ = 8539465680.

The previous prime is 8539465661. The next prime is 8539465723. The reversal of 8539465681 is 1865649358.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8534988225 + 4477456 = 92385^2 + 2116^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8539465681 is a prime.

It is a super-2 number, since 2×8539465681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (8539465631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4269732840 + 4269732841.

It is an arithmetic number, because the mean of its divisors is an integer number (4269732841).

Almost surely, 2^8539465681 is an apocalyptic number.

It is an amenable number.

8539465681 is a deficient number, since it is larger than the sum of its proper divisors (1).

8539465681 is an equidigital number, since it uses as much as digits as its factorization.

8539465681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6220800, while the sum is 55.

The square root of 8539465681 is about 92409.2294145991. The cubic root of 8539465681 is about 2043.9812104059.

The spelling of 8539465681 in words is "eight billion, five hundred thirty-nine million, four hundred sixty-five thousand, six hundred eighty-one".