203401409 has 2 divisors, whose sum is σ = 203401410. Its totient is φ = 203401408.

The previous prime is 203401381. The next prime is 203401411. The reversal of 203401409 is 904104302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 153388225 + 50013184 = 12385^2 + 7072^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-203401409 is a prime.

Together with 203401411, 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 (203401609) 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, 101700704 + 101700705.

It is an arithmetic number, because the mean of its divisors is an integer number (101700705).

Almost surely, 2^203401409 is an apocalyptic number.

It is an amenable number.

203401409 is a deficient number, since it is larger than the sum of its proper divisors (1).

203401409 is an equidigital number, since it uses as much as digits as its factorization.

203401409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 203401409 is about 14261.8865862830. The cubic root of 203401409 is about 588.1001890534.

The spelling of 203401409 in words is "two hundred three million, four hundred one thousand, four hundred nine".