203207421 has 4 divisors (see below), whose sum is σ = 270943232. Its totient is φ = 135471612.

The previous prime is 203207401. The next prime is 203207429. The reversal of 203207421 is 124702302.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 203207421 - 2¹³ = 203199229 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (203207429) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33867901 + ... + 33867906.

It is an arithmetic number, because the mean of its divisors is an integer number (67735808).

Almost surely, 2^203207421 is an apocalyptic number.

It is an amenable number.

203207421 is a deficient number, since it is larger than the sum of its proper divisors (67735811).

203207421 is an equidigital number, since it uses as much as digits as its factorization.

203207421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67735810.

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 203207421 is about 14255.0840404397. The cubic root of 203207421 is about 587.9131686071.

Adding to 203207421 its reverse (124702302), we get a palindrome (327909723).

The spelling of 203207421 in words is "two hundred three million, two hundred seven thousand, four hundred twenty-one".