21242236404 has 12 divisors (see below), whose sum is σ = 49565218304. Its totient is φ = 7080745464.

The previous prime is 21242236403. The next prime is 21242236429. The reversal of 21242236404 is 40463224212.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21242236403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 885093172 + ... + 885093195.

Almost surely, 2^21242236404 is an apocalyptic number.

It is an amenable number.

21242236404 is an abundant number, since it is smaller than the sum of its proper divisors (28322981900).

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

21242236404 is a wasteful number, since it uses less digits than its factorization.

21242236404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1770186374 (or 1770186372 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 30.

The spelling of 21242236404 in words is "twenty-one billion, two hundred forty-two million, two hundred thirty-six thousand, four hundred four".