800079661 has 2 divisors, whose sum is σ = 800079662. Its totient is φ = 800079660.

The previous prime is 800079659. The next prime is 800079677. The reversal of 800079661 is 166970008.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 635342436 + 164737225 = 25206^2 + 12835^2 .

It is a cyclic number.

It is not a de Polignac number, because 800079661 - 2¹ = 800079659 is a prime.

Together with 800079659, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 800079661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (800079641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 400039830 + 400039831.

It is an arithmetic number, because the mean of its divisors is an integer number (400039831).

Almost surely, 2^800079661 is an apocalyptic number.

It is an amenable number.

800079661 is a deficient number, since it is larger than the sum of its proper divisors (1).

800079661 is an equidigital number, since it uses as much as digits as its factorization.

800079661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 800079661 is about 28285.6794332397. The cubic root of 800079661 is about 928.3485785005.

The spelling of 800079661 in words is "eight hundred million, seventy-nine thousand, six hundred sixty-one".