81566190606301 has 2 divisors, whose sum is σ = 81566190606302. Its totient is φ = 81566190606300.

The previous prime is 81566190606233. The next prime is 81566190606317. The reversal of 81566190606301 is 10360609166518.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73284745543801 + 8281445062500 = 8560651^2 + 2877750^2 .

It is a cyclic number.

It is not a de Polignac number, because 81566190606301 - 2¹¹ = 81566190604253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81566190306301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40783095303150 + 40783095303151.

It is an arithmetic number, because the mean of its divisors is an integer number (40783095303151).

Almost surely, 2^{81566190606301} is an apocalyptic number.

It is an amenable number.

81566190606301 is a deficient number, since it is larger than the sum of its proper divisors (1).

81566190606301 is an equidigital number, since it uses as much as digits as its factorization.

81566190606301 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1399680, while the sum is 52.

The spelling of 81566190606301 in words is "eighty-one trillion, five hundred sixty-six billion, one hundred ninety million, six hundred six thousand, three hundred one".