84280309 has 2 divisors, whose sum is σ = 84280310. Its totient is φ = 84280308.

The previous prime is 84280277. The next prime is 84280319. The reversal of 84280309 is 90308248.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49210225 + 35070084 = 7015^2 + 5922^2 .

It is a cyclic number.

It is not a de Polignac number, because 84280309 - 2⁵ = 84280277 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84280319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42140154 + 42140155.

It is an arithmetic number, because the mean of its divisors is an integer number (42140155).

Almost surely, 2^84280309 is an apocalyptic number.

It is an amenable number.

84280309 is a deficient number, since it is larger than the sum of its proper divisors (1).

84280309 is an equidigital number, since it uses as much as digits as its factorization.

84280309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13824, while the sum is 34.

The square root of 84280309 is about 9180.4307633139. The cubic root of 84280309 is about 438.4385233660.

The spelling of 84280309 in words is "eighty-four million, two hundred eighty thousand, three hundred nine".