21455342242 has 16 divisors (see below), whose sum is σ = 32718780864. Its totient is φ = 10549170000.

The previous prime is 21455342197. The next prime is 21455342243. The reversal of 21455342242 is 24224355412.

It is a junction number, because it is equal to n+sod(n) for n = 21455342198 and 21455342207.

It is not an unprimeable number, because it can be changed into a prime (21455342243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 523267 + ... + 562777.

It is an arithmetic number, because the mean of its divisors is an integer number (2044923804).

Almost surely, 2^21455342242 is an apocalyptic number.

21455342242 is a deficient number, since it is larger than the sum of its proper divisors (11263438622).

21455342242 is a wasteful number, since it uses less digits than its factorization.

21455342242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44025.

The product of its digits is 76800, while the sum is 34.

Adding to 21455342242 its reverse (24224355412), we get a palindrome (45679697654).

The spelling of 21455342242 in words is "twenty-one billion, four hundred fifty-five million, three hundred forty-two thousand, two hundred forty-two".