20210421403 has 2 divisors, whose sum is σ = 20210421404. Its totient is φ = 20210421402.

The previous prime is 20210421397. The next prime is 20210421419. The reversal of 20210421403 is 30412401202.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20210421403 is a prime.

It is a super-2 number, since 2×20210421403² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20210431403) 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, 10105210701 + 10105210702.

It is an arithmetic number, because the mean of its divisors is an integer number (10105210702).

Almost surely, 2^20210421403 is an apocalyptic number.

20210421403 is a deficient number, since it is larger than the sum of its proper divisors (1).

20210421403 is an equidigital number, since it uses as much as digits as its factorization.

20210421403 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 20210421403 its reverse (30412401202), we get a palindrome (50622822605).

The spelling of 20210421403 in words is "twenty billion, two hundred ten million, four hundred twenty-one thousand, four hundred three".