421204243 has 2 divisors, whose sum is σ = 421204244. Its totient is φ = 421204242.

The previous prime is 421204229. The next prime is 421204247. The reversal of 421204243 is 342402124.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-421204243 is a prime.

It is not a weakly prime, because it can be changed into another prime (421204247) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210602121 + 210602122.

It is an arithmetic number, because the mean of its divisors is an integer number (210602122).

Almost surely, 2^421204243 is an apocalyptic number.

421204243 is a deficient number, since it is larger than the sum of its proper divisors (1).

421204243 is an equidigital number, since it uses as much as digits as its factorization.

421204243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 22.

The square root of 421204243 is about 20523.2610225568. The cubic root of 421204243 is about 749.6023035243.

Adding to 421204243 its reverse (342402124), we get a palindrome (763606367).

The spelling of 421204243 in words is "four hundred twenty-one million, two hundred four thousand, two hundred forty-three".