2128523909 has 2 divisors, whose sum is σ = 2128523910. Its totient is φ = 2128523908.

The previous prime is 2128523899. The next prime is 2128523959. The reversal of 2128523909 is 9093258212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1844702500 + 283821409 = 42950^2 + 16847^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2128523909 is a prime.

It is a super-2 number, since 2×2128523909² = 9061228062369280562, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2128523959) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1064261954 + 1064261955.

It is an arithmetic number, because the mean of its divisors is an integer number (1064261955).

Almost surely, 2^2128523909 is an apocalyptic number.

It is an amenable number.

2128523909 is a deficient number, since it is larger than the sum of its proper divisors (1).

2128523909 is an equidigital number, since it uses as much as digits as its factorization.

2128523909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 77760, while the sum is 41.

The square root of 2128523909 is about 46135.9286131752. The cubic root of 2128523909 is about 1286.3510665699.

The spelling of 2128523909 in words is "two billion, one hundred twenty-eight million, five hundred twenty-three thousand, nine hundred nine".