21842521838 has 4 divisors (see below), whose sum is σ = 32763782760. Its totient is φ = 10921260918.

The previous prime is 21842521817. The next prime is 21842521853. The reversal of 21842521838 is 83812524812.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5460630458 + ... + 5460630461.

It is an arithmetic number, because the mean of its divisors is an integer number (8190945690).

Almost surely, 2^21842521838 is an apocalyptic number.

21842521838 is a deficient number, since it is larger than the sum of its proper divisors (10921260922).

21842521838 is a wasteful number, since it uses less digits than its factorization.

21842521838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10921260921.

The product of its digits is 245760, while the sum is 44.

The spelling of 21842521838 in words is "twenty-one billion, eight hundred forty-two million, five hundred twenty-one thousand, eight hundred thirty-eight".