2155009 has 2 divisors, whose sum is σ = 2155010. Its totient is φ = 2155008.

The previous prime is 2155007. The next prime is 2155057. The reversal of 2155009 is 9005512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2131600 + 23409 = 1460^2 + 153^2 .

It is a cyclic number.

It is not a de Polignac number, because 2155009 - 2¹ = 2155007 is a prime.

Together with 2155007, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (2155003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1077504 + 1077505.

It is an arithmetic number, because the mean of its divisors is an integer number (1077505).

2^2155009 is an apocalyptic number.

It is an amenable number.

2155009 is a deficient number, since it is larger than the sum of its proper divisors (1).

2155009 is an equidigital number, since it uses as much as digits as its factorization.

2155009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 450, while the sum is 22.

The square root of 2155009 is about 1467.9948909993. The cubic root of 2155009 is about 129.1664418079.

The spelling of 2155009 in words is "two million, one hundred fifty-five thousand, nine".