2155984309 has 2 divisors, whose sum is σ = 2155984310. Its totient is φ = 2155984308.

The previous prime is 2155984307. The next prime is 2155984331. The reversal of 2155984309 is 9034895512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1949487409 + 206496900 = 44153^2 + 14370^2 .

It is a cyclic number.

It is not a de Polignac number, because 2155984309 - 2¹ = 2155984307 is a prime.

Together with 2155984307, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2155984307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1077992154 + 1077992155.

It is an arithmetic number, because the mean of its divisors is an integer number (1077992155).

Almost surely, 2^2155984309 is an apocalyptic number.

It is an amenable number.

2155984309 is a deficient number, since it is larger than the sum of its proper divisors (1).

2155984309 is an equidigital number, since it uses as much as digits as its factorization.

2155984309 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 388800, while the sum is 46.

The square root of 2155984309 is about 46432.5780998643. The cubic root of 2155984309 is about 1291.8592481906.

The spelling of 2155984309 in words is "two billion, one hundred fifty-five million, nine hundred eighty-four thousand, three hundred nine".