203420905 has 8 divisors (see below), whose sum is σ = 246265992. Its totient is φ = 161296128.

The previous prime is 203420887. The next prime is 203420927. The reversal of 203420905 is 509024302.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 5934096 + 197486809 = 2436^2 + 14053^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 203420905 - 2⁵ = 203420873 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 203420905.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 179454 + ... + 180583.

It is an arithmetic number, because the mean of its divisors is an integer number (30783249).

Almost surely, 2^203420905 is an apocalyptic number.

It is an amenable number.

203420905 is a deficient number, since it is larger than the sum of its proper divisors (42845087).

203420905 is a wasteful number, since it uses less digits than its factorization.

203420905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360155.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 203420905 is about 14262.5700699418. The cubic root of 203420905 is about 588.1189782300.

The spelling of 203420905 in words is "two hundred three million, four hundred twenty thousand, nine hundred five".