84689509 has 2 divisors, whose sum is σ = 84689510. Its totient is φ = 84689508.

The previous prime is 84689459. The next prime is 84689513. The reversal of 84689509 is 90598648.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51165409 + 33524100 = 7153^2 + 5790^2 .

It is a cyclic number.

It is not a de Polignac number, because 84689509 - 2⁹ = 84688997 is a prime.

It is a super-2 number, since 2×84689509² = 14344625869322162, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84689609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42344754 + 42344755.

It is an arithmetic number, because the mean of its divisors is an integer number (42344755).

Almost surely, 2^84689509 is an apocalyptic number.

It is an amenable number.

84689509 is a deficient number, since it is larger than the sum of its proper divisors (1).

84689509 is an equidigital number, since it uses as much as digits as its factorization.

84689509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 622080, while the sum is 49.

The square root of 84689509 is about 9202.6903131639. The cubic root of 84689509 is about 439.1469508716.

The spelling of 84689509 in words is "eighty-four million, six hundred eighty-nine thousand, five hundred nine".