21802218044 has 6 divisors (see below), whose sum is σ = 38153881584. Its totient is φ = 10901109020.

The previous prime is 21802218043. The next prime is 21802218047. The reversal of 21802218044 is 44081220812.

It is a self number, because there is not a number n which added to its sum of digits gives 21802218044.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21802218043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2725277252 + ... + 2725277259.

It is an arithmetic number, because the mean of its divisors is an integer number (6358980264).

Almost surely, 2^21802218044 is an apocalyptic number.

It is an amenable number.

21802218044 is a deficient number, since it is larger than the sum of its proper divisors (16351663540).

21802218044 is a wasteful number, since it uses less digits than its factorization.

21802218044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5450554515 (or 5450554513 counting only the distinct ones).

The product of its (nonzero) digits is 8192, while the sum is 32.

Adding to 21802218044 its reverse (44081220812), we get a palindrome (65883438856).

The spelling of 21802218044 in words is "twenty-one billion, eight hundred two million, two hundred eighteen thousand, forty-four".