21004213120 has 64 divisors (see below), whose sum is σ = 54778051440. Its totient is φ = 7637893120.

The previous prime is 21004213093. The next prime is 21004213151. The reversal of 21004213120 is 2131240012.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 21004213094 and 21004213103.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1484737 + ... + 1498816.

Almost surely, 2^21004213120 is an apocalyptic number.

21004213120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21004213120 is an abundant number, since it is smaller than the sum of its proper divisors (33773838320).

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

21004213120 is a wasteful number, since it uses less digits than its factorization.

21004213120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2983583 (or 2983571 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21004213120 its reverse (2131240012), we get a palindrome (23135453132).

The spelling of 21004213120 in words is "twenty-one billion, four million, two hundred thirteen thousand, one hundred twenty".