6445409 has 2 divisors, whose sum is σ = 6445410. Its totient is φ = 6445408.

The previous prime is 6445403. The next prime is 6445433. The reversal of 6445409 is 9045446.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5626384 + 819025 = 2372^2 + 905^2 .

It is a cyclic number.

It is not a de Polignac number, because 6445409 - 2⁴ = 6445393 is a prime.

It is not a weakly prime, because it can be changed into another prime (6445403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3222704 + 3222705.

It is an arithmetic number, because the mean of its divisors is an integer number (3222705).

Almost surely, 2^6445409 is an apocalyptic number.

It is an amenable number.

6445409 is a deficient number, since it is larger than the sum of its proper divisors (1).

6445409 is an equidigital number, since it uses as much as digits as its factorization.

6445409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 32.

The square root of 6445409 is about 2538.7810067038. The cubic root of 6445409 is about 186.1016228886.

The spelling of 6445409 in words is "six million, four hundred forty-five thousand, four hundred nine".