21400214421 has 4 divisors (see below), whose sum is σ = 28533619232. Its totient is φ = 14266809612.

The previous prime is 21400214419. The next prime is 21400214453. The reversal of 21400214421 is 12441200412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21400214421 - 2¹ = 21400214419 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 (21400214821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3566702401 + ... + 3566702406.

It is an arithmetic number, because the mean of its divisors is an integer number (7133404808).

Almost surely, 2^21400214421 is an apocalyptic number.

It is an amenable number.

21400214421 is a deficient number, since it is larger than the sum of its proper divisors (7133404811).

21400214421 is an equidigital number, since it uses as much as digits as its factorization.

21400214421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7133404810.

The product of its (nonzero) digits is 512, while the sum is 21.

Adding to 21400214421 its reverse (12441200412), we get a palindrome (33841414833).

The spelling of 21400214421 in words is "twenty-one billion, four hundred million, two hundred fourteen thousand, four hundred twenty-one".