203212121 has 4 divisors (see below), whose sum is σ = 232242432. Its totient is φ = 174181812.

The previous prime is 203212117. The next prime is 203212133. The reversal of 203212121 is 121212302.

It is a happy number.

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, and also an emirpimes, since its reverse is a distinct semiprime: 121212302 = 2 ⋅60606151.

It is not a de Polignac number, because 203212121 - 2² = 203212117 is a prime.

It is a super-2 number, since 2×203212121² = 82590332242637282, which contains 22 as substring.

It is a Duffinian number.

203212121 is a modest number, since divided by 212121 gives 203 as remainder.

It is a junction number, because it is equal to n+sod(n) for n = 203212096 and 203212105.

It is not an unprimeable number, because it can be changed into a prime (203212111) 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 in 3 ways as a sum of consecutive naturals, for example, 14515145 + ... + 14515158.

It is an arithmetic number, because the mean of its divisors is an integer number (58060608).

Almost surely, 2^203212121 is an apocalyptic number.

It is an amenable number.

203212121 is a deficient number, since it is larger than the sum of its proper divisors (29030311).

203212121 is an equidigital number, since it uses as much as digits as its factorization.

203212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29030310.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 203212121 is about 14255.2488929517. The cubic root of 203212121 is about 587.9177012017.

Adding to 203212121 its reverse (121212302), we get a palindrome (324424423).

The spelling of 203212121 in words is "two hundred three million, two hundred twelve thousand, one hundred twenty-one".