21242111604 has 96 divisors (see below), whose sum is σ = 57042026496. Its totient is φ = 6026824320.

The previous prime is 21242111593. The next prime is 21242111621. The reversal of 21242111604 is 40611124212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 16251919 + ... + 16253225.

It is an arithmetic number, because the mean of its divisors is an integer number (594187776).

Almost surely, 2^21242111604 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21242111604, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28521013248).

21242111604 is an abundant number, since it is smaller than the sum of its proper divisors (35799914892).

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

21242111604 is a wasteful number, since it uses less digits than its factorization.

21242111604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2525 (or 2523 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 24.

Adding to 21242111604 its reverse (40611124212), we get a palindrome (61853235816).

The spelling of 21242111604 in words is "twenty-one billion, two hundred forty-two million, one hundred eleven thousand, six hundred four".