21103133421 has 8 divisors (see below), whose sum is σ = 28139421184. Its totient is φ = 14067800640.

The previous prime is 21103133399. The next prime is 21103133431. The reversal of 21103133421 is 12433130112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-21103133421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21103133431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 185485 + ... + 276786.

It is an arithmetic number, because the mean of its divisors is an integer number (3517427648).

Almost surely, 2^21103133421 is an apocalyptic number.

It is an amenable number.

21103133421 is a deficient number, since it is larger than the sum of its proper divisors (7036287763).

21103133421 is a wasteful number, since it uses less digits than its factorization.

21103133421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 477491.

The product of its (nonzero) digits is 432, while the sum is 21.

Adding to 21103133421 its reverse (12433130112), we get a palindrome (33536263533).

The spelling of 21103133421 in words is "twenty-one billion, one hundred three million, one hundred thirty-three thousand, four hundred twenty-one".