21124342442 has 16 divisors (see below), whose sum is σ = 36709230912. Its totient is φ = 8929271520.

The previous prime is 21124342423. The next prime is 21124342451. The reversal of 21124342442 is 24424342112.

It is a happy number.

It is an unprimeable number.

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, 10333784 + ... + 10335827.

It is an arithmetic number, because the mean of its divisors is an integer number (2294326932).

Almost surely, 2^21124342442 is an apocalyptic number.

21124342442 is a deficient number, since it is larger than the sum of its proper divisors (15584888470).

21124342442 is a wasteful number, since it uses less digits than its factorization.

21124342442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20669693.

The product of its digits is 12288, while the sum is 29.

Adding to 21124342442 its reverse (24424342112), we get a palindrome (45548684554).

The spelling of 21124342442 in words is "twenty-one billion, one hundred twenty-four million, three hundred forty-two thousand, four hundred forty-two".