81522970214409 has 6 divisors (see below), whose sum is σ = 117755401420826. Its totient is φ = 54348646809600.

The previous prime is 81522970214327. The next prime is 81522970214417. The reversal of 81522970214409 is 90441207922518.

81522970214409 is a `hidden beast` number, since 8 + 1 + 5 + 229 + 7 + 0 + 2 + 1 + 4 + 409 = 666.

It can be written as a sum of positive squares in only one way, i.e., 72595256481225 + 8927713733184 = 8520285^2 + 2987928^2 .

It is not a de Polignac number, because 81522970214409 - 2⁷ = 81522970214281 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81522970214429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4529053900792 + ... + 4529053900809.

Almost surely, 2^{81522970214409} is an apocalyptic number.

It is an amenable number.

81522970214409 is a deficient number, since it is larger than the sum of its proper divisors (36232431206417).

81522970214409 is a wasteful number, since it uses less digits than its factorization.

81522970214409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9058107801607 (or 9058107801604 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The spelling of 81522970214409 in words is "eighty-one trillion, five hundred twenty-two billion, nine hundred seventy million, two hundred fourteen thousand, four hundred nine".