204111421 has 2 divisors, whose sum is σ = 204111422. Its totient is φ = 204111420.

The previous prime is 204111419. The next prime is 204111451. The reversal of 204111421 is 124111402.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 182628196 + 21483225 = 13514^2 + 4635^2 .

It is a cyclic number.

It is not a de Polignac number, because 204111421 - 2¹ = 204111419 is a prime.

It is a super-2 number, since 2×204111421² = 83322944365278482, which contains 22 as substring.

Together with 204111419, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 204111395 and 204111404.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (204111451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102055710 + 102055711.

It is an arithmetic number, because the mean of its divisors is an integer number (102055711).

Almost surely, 2^204111421 is an apocalyptic number.

It is an amenable number.

204111421 is a deficient number, since it is larger than the sum of its proper divisors (1).

204111421 is an equidigital number, since it uses as much as digits as its factorization.

204111421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 204111421 is about 14286.7568398150. The cubic root of 204111421 is about 588.7836869007.

Adding to 204111421 its reverse (124111402), we get a palindrome (328222823).

The spelling of 204111421 in words is "two hundred four million, one hundred eleven thousand, four hundred twenty-one".