85166589281 has 2 divisors, whose sum is σ = 85166589282. Its totient is φ = 85166589280.

The previous prime is 85166589271. The next prime is 85166589283. The reversal of 85166589281 is 18298566158.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 85141987681 + 24601600 = 291791^2 + 4960^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-85166589281 is a prime.

It is a super-2 number, since 2×85166589281² (a number of 23 digits) contains 22 as substring.

Together with 85166589283, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 85166589281.

It is not a weakly prime, because it can be changed into another prime (85166589283) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42583294640 + 42583294641.

It is an arithmetic number, because the mean of its divisors is an integer number (42583294641).

Almost surely, 2^85166589281 is an apocalyptic number.

It is an amenable number.

85166589281 is a deficient number, since it is larger than the sum of its proper divisors (1).

85166589281 is an equidigital number, since it uses as much as digits as its factorization.

85166589281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8294400, while the sum is 59.

The spelling of 85166589281 in words is "eighty-five billion, one hundred sixty-six million, five hundred eighty-nine thousand, two hundred eighty-one".