2151509 has 2 divisors, whose sum is σ = 2151510. Its totient is φ = 2151508.

The previous prime is 2151497. The next prime is 2151511. The reversal of 2151509 is 9051512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1380625 + 770884 = 1175^2 + 878^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2151509 is a prime.

Together with 2151511, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2150509) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1075754 + 1075755.

It is an arithmetic number, because the mean of its divisors is an integer number (1075755).

2^2151509 is an apocalyptic number.

It is an amenable number.

2151509 is a deficient number, since it is larger than the sum of its proper divisors (1).

2151509 is an equidigital number, since it uses as much as digits as its factorization.

2151509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 450, while the sum is 23.

The square root of 2151509 is about 1466.8023043342. The cubic root of 2151509 is about 129.0964765141.

The spelling of 2151509 in words is "two million, one hundred fifty-one thousand, five hundred nine".