21440420343 has 12 divisors (see below), whose sum is σ = 31001207328. Its totient is φ = 14278977600.

The previous prime is 21440420327. The next prime is 21440420369. The reversal of 21440420343 is 34302404412.

It is a happy number.

21440420343 is a `hidden beast` number, since 2 + 14 + 404 + 203 + 43 = 666.

It is not a de Polignac number, because 21440420343 - 2⁴ = 21440420327 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21440420143) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1210383 + ... + 1227968.

It is an arithmetic number, because the mean of its divisors is an integer number (2583433944).

Almost surely, 2^21440420343 is an apocalyptic number.

21440420343 is a deficient number, since it is larger than the sum of its proper divisors (9560786985).

21440420343 is a wasteful number, since it uses less digits than its factorization.

21440420343 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2439334 (or 2439331 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 27.

Adding to 21440420343 its reverse (34302404412), we get a palindrome (55742824755).

The spelling of 21440420343 in words is "twenty-one billion, four hundred forty million, four hundred twenty thousand, three hundred forty-three".