82789409 has 2 divisors, whose sum is σ = 82789410. Its totient is φ = 82789408.

The previous prime is 82789391. The next prime is 82789417. The reversal of 82789409 is 90498728.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62853184 + 19936225 = 7928^2 + 4465^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-82789409 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (82789009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41394704 + 41394705.

It is an arithmetic number, because the mean of its divisors is an integer number (41394705).

Almost surely, 2^82789409 is an apocalyptic number.

It is an amenable number.

82789409 is a deficient number, since it is larger than the sum of its proper divisors (1).

82789409 is an equidigital number, since it uses as much as digits as its factorization.

82789409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 290304, while the sum is 47.

The square root of 82789409 is about 9098.8685560349. The cubic root of 82789409 is about 435.8378338781.

The spelling of 82789409 in words is "eighty-two million, seven hundred eighty-nine thousand, four hundred nine".