21004442304 has 28 divisors (see below), whose sum is σ = 55574254104. Its totient is φ = 7001480704.

The previous prime is 21004442279. The next prime is 21004442309. The reversal of 21004442304 is 40324440012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (21004442309) 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, 54698877 + ... + 54699260.

Almost surely, 2^21004442304 is an apocalyptic number.

21004442304 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21004442304 is an abundant number, since it is smaller than the sum of its proper divisors (34569811800).

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

21004442304 is a wasteful number, since it uses less digits than its factorization.

21004442304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109398152 (or 109398142 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 24.

Adding to 21004442304 its reverse (40324440012), we get a palindrome (61328882316).

The spelling of 21004442304 in words is "twenty-one billion, four million, four hundred forty-two thousand, three hundred four".