83779565209 has 2 divisors, whose sum is σ = 83779565210. Its totient is φ = 83779565208.

The previous prime is 83779565173. The next prime is 83779565213. The reversal of 83779565209 is 90256597738.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 45077659225 + 38701905984 = 212315^2 + 196728^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-83779565209 is a prime.

It is not a weakly prime, because it can be changed into another prime (83779565609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41889782604 + 41889782605.

It is an arithmetic number, because the mean of its divisors is an integer number (41889782605).

Almost surely, 2^83779565209 is an apocalyptic number.

It is an amenable number.

83779565209 is a deficient number, since it is larger than the sum of its proper divisors (1).

83779565209 is an equidigital number, since it uses as much as digits as its factorization.

83779565209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28576800, while the sum is 61.

The spelling of 83779565209 in words is "eighty-three billion, seven hundred seventy-nine million, five hundred sixty-five thousand, two hundred nine".