21143144242 has 16 divisors (see below), whose sum is σ = 35165052864. Its totient is φ = 9452970000.

The previous prime is 21143144237. The next prime is 21143144261. The reversal of 21143144242 is 24244134112.

It is a self number, because there is not a number n which added to its sum of digits gives 21143144242.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7876134 + ... + 7878817.

It is an arithmetic number, because the mean of its divisors is an integer number (2197815804).

Almost surely, 2^21143144242 is an apocalyptic number.

21143144242 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21143144242 is a deficient number, since it is larger than the sum of its proper divisors (14021908622).

21143144242 is a wasteful number, since it uses less digits than its factorization.

21143144242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15755025.

The product of its digits is 6144, while the sum is 28.

Adding to 21143144242 its reverse (24244134112), we get a palindrome (45387278354).

The spelling of 21143144242 in words is "twenty-one billion, one hundred forty-three million, one hundred forty-four thousand, two hundred forty-two".