81538394600969 has 2 divisors, whose sum is σ = 81538394600970. Its totient is φ = 81538394600968.

The previous prime is 81538394600963. The next prime is 81538394601061. The reversal of 81538394600969 is 96900649383518.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 68629377961225 + 12909016639744 = 8284285^2 + 3592912^2 .

It is a cyclic number.

It is not a de Polignac number, because 81538394600969 - 2⁴ = 81538394600953 is a prime.

It is a super-2 number, since 2×81538394600969² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (81538394600963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40769197300484 + 40769197300485.

It is an arithmetic number, because the mean of its divisors is an integer number (40769197300485).

Almost surely, 2^{81538394600969} is an apocalyptic number.

It is an amenable number.

81538394600969 is a deficient number, since it is larger than the sum of its proper divisors (1).

81538394600969 is an equidigital number, since it uses as much as digits as its factorization.

81538394600969 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 302330880, while the sum is 71.

The spelling of 81538394600969 in words is "eighty-one trillion, five hundred thirty-eight billion, three hundred ninety-four million, six hundred thousand, nine hundred sixty-nine".