21221140404 has 12 divisors (see below), whose sum is σ = 49515994304. Its totient is φ = 7073713464.

The previous prime is 21221140393. The next prime is 21221140411. The reversal of 21221140404 is 40404112212.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 884214172 + ... + 884214195.

Almost surely, 2^21221140404 is an apocalyptic number.

It is an amenable number.

21221140404 is an abundant number, since it is smaller than the sum of its proper divisors (28294853900).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21221140404 is a wasteful number, since it uses less digits than its factorization.

21221140404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1768428374 (or 1768428372 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 21.

Adding to 21221140404 its reverse (40404112212), we get a palindrome (61625252616).

The spelling of 21221140404 in words is "twenty-one billion, two hundred twenty-one million, one hundred forty thousand, four hundred four".