654397409 has 2 divisors, whose sum is σ = 654397410. Its totient is φ = 654397408.

The previous prime is 654397343. The next prime is 654397417. The reversal of 654397409 is 904793456.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 654336400 + 61009 = 25580^2 + 247^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-654397409 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (654397489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 327198704 + 327198705.

It is an arithmetic number, because the mean of its divisors is an integer number (327198705).

Almost surely, 2^654397409 is an apocalyptic number.

It is an amenable number.

654397409 is a deficient number, since it is larger than the sum of its proper divisors (1).

654397409 is an equidigital number, since it uses as much as digits as its factorization.

654397409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 816480, while the sum is 47.

The square root of 654397409 is about 25581.1924858870. The cubic root of 654397409 is about 868.1881564716.

The spelling of 654397409 in words is "six hundred fifty-four million, three hundred ninety-seven thousand, four hundred nine".