21344442142 has 4 divisors (see below), whose sum is σ = 32016663216. Its totient is φ = 10672221070.

The previous prime is 21344442137. The next prime is 21344442173. The reversal of 21344442142 is 24124444312.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent 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 as a sum of consecutive naturals, namely, 5336110534 + ... + 5336110537.

It is an arithmetic number, because the mean of its divisors is an integer number (8004165804).

Almost surely, 2^21344442142 is an apocalyptic number.

21344442142 is a deficient number, since it is larger than the sum of its proper divisors (10672221074).

21344442142 is a wasteful number, since it uses less digits than its factorization.

21344442142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10672221073.

The product of its digits is 24576, while the sum is 31.

Adding to 21344442142 its reverse (24124444312), we get a palindrome (45468886454).

The spelling of 21344442142 in words is "twenty-one billion, three hundred forty-four million, four hundred forty-two thousand, one hundred forty-two".