421000403 has 2 divisors, whose sum is σ = 421000404. Its totient is φ = 421000402.

The previous prime is 421000399. The next prime is 421000439. The reversal of 421000403 is 304000124.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 421000403 - 2² = 421000399 is a prime.

It is not a weakly prime, because it can be changed into another prime (421000483) by changing a digit.

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 as a sum of consecutive naturals, namely, 210500201 + 210500202.

It is an arithmetic number, because the mean of its divisors is an integer number (210500202).

Almost surely, 2^421000403 is an apocalyptic number.

421000403 is a deficient number, since it is larger than the sum of its proper divisors (1).

421000403 is an equidigital number, since it uses as much as digits as its factorization.

421000403 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 14.

The square root of 421000403 is about 20518.2943491899. The cubic root of 421000403 is about 749.4813617314.

Adding to 421000403 its reverse (304000124), we get a palindrome (725000527).

The spelling of 421000403 in words is "four hundred twenty-one million, four hundred three", and thus it is an aban number.