869992817549 has 2 divisors, whose sum is σ = 869992817550. Its totient is φ = 869992817548.

The previous prime is 869992817539. The next prime is 869992817591. The reversal of 869992817549 is 945718299968.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 678822744649 + 191170072900 = 823907^2 + 437230^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-869992817549 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 869992817549.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (869992817539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 434996408774 + 434996408775.

It is an arithmetic number, because the mean of its divisors is an integer number (434996408775).

Almost surely, 2^869992817549 is an apocalyptic number.

It is an amenable number.

869992817549 is a deficient number, since it is larger than the sum of its proper divisors (1).

869992817549 is an equidigital number, since it uses as much as digits as its factorization.

869992817549 is an evil number, because the sum of its binary digits is even.

The product of its digits is 705438720, while the sum is 77.

The spelling of 869992817549 in words is "eight hundred sixty-nine billion, nine hundred ninety-two million, eight hundred seventeen thousand, five hundred forty-nine".