21421330403 has 32 divisors (see below), whose sum is σ = 25021275840. Its totient is φ = 18123264000.

The previous prime is 21421330397. The next prime is 21421330421. The reversal of 21421330403 is 30403312412.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21421330403 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21421330433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15510773 + ... + 15512153.

It is an arithmetic number, because the mean of its divisors is an integer number (781914870).

Almost surely, 2^21421330403 is an apocalyptic number.

21421330403 is a deficient number, since it is larger than the sum of its proper divisors (3599945437).

21421330403 is a wasteful number, since it uses less digits than its factorization.

21421330403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2279.

The product of its (nonzero) digits is 1728, while the sum is 23.

Adding to 21421330403 its reverse (30403312412), we get a palindrome (51824642815).

The spelling of 21421330403 in words is "twenty-one billion, four hundred twenty-one million, three hundred thirty thousand, four hundred three".