817309252242 has 270 divisors, whose sum is σ = 2175612778053. Its totient is φ = 228661102656.

The previous prime is 817309252241. The next prime is 817309252261. The reversal of 817309252242 is 242252903718.

817309252242 is a `hidden beast` number, since 8 + 1 + 7 + 30 + 92 + 522 + 4 + 2 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 813551684841 + 3757567401 = 901971^2 + 61299^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=639261.

It is not an unprimeable number, because it can be changed into a prime (817309252241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 5879922609 + ... + 5879922747.

Almost surely, 2^817309252242 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 817309252242

817309252242 is an abundant number, since it is smaller than the sum of its proper divisors (1358303525811).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

817309252242 is an equidigital number, since it uses as much as digits as its factorization.

817309252242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 452 (or 224 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The spelling of 817309252242 in words is "eight hundred seventeen billion, three hundred nine million, two hundred fifty-two thousand, two hundred forty-two".