21404220343 has 6 divisors (see below), whose sum is σ = 23526953072. Its totient is φ = 19458382020.

The previous prime is 21404220301. The next prime is 21404220367. The reversal of 21404220343 is 34302240412.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-21404220343 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 (21404220743) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 88447071 + ... + 88447312.

Almost surely, 2^21404220343 is an apocalyptic number.

21404220343 is a deficient number, since it is larger than the sum of its proper divisors (2122732729).

21404220343 is a wasteful number, since it uses less digits than its factorization.

21404220343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176894405 (or 176894394 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 25.

Adding to 21404220343 its reverse (34302240412), we get a palindrome (55706460755).

The spelling of 21404220343 in words is "twenty-one billion, four hundred four million, two hundred twenty thousand, three hundred forty-three".