128822509 has 2 divisors, whose sum is σ = 128822510. Its totient is φ = 128822508.

The previous prime is 128822503. The next prime is 128822513. The reversal of 128822509 is 905228821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 128822500 + 9 = 11350^2 + 3^2 .

It is a cyclic number.

It is not a de Polignac number, because 128822509 - 2³ = 128822501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128822501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64411254 + 64411255.

It is an arithmetic number, because the mean of its divisors is an integer number (64411255).

Almost surely, 2^128822509 is an apocalyptic number.

It is an amenable number.

128822509 is a deficient number, since it is larger than the sum of its proper divisors (1).

128822509 is an equidigital number, since it uses as much as digits as its factorization.

128822509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23040, while the sum is 37.

The square root of 128822509 is about 11350.0003964758. Note that the first 3 decimals coincide. The cubic root of 128822509 is about 505.0455914137.

The spelling of 128822509 in words is "one hundred twenty-eight million, eight hundred twenty-two thousand, five hundred nine".