21421304120 has 64 divisors (see below), whose sum is σ = 49473663840. Its totient is φ = 8344512000.

The previous prime is 21421304101. The next prime is 21421304131. The reversal of 21421304120 is 2140312412.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 21421304092 and 21421304101.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 202979 + ... + 289901.

Almost surely, 2^21421304120 is an apocalyptic number.

21421304120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21421304120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24736831920).

21421304120 is an abundant number, since it is smaller than the sum of its proper divisors (28052359720).

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

21421304120 is a wasteful number, since it uses less digits than its factorization.

21421304120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87096 (or 87092 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21421304120 its reverse (2140312412), we get a palindrome (23561616532).

The spelling of 21421304120 in words is "twenty-one billion, four hundred twenty-one million, three hundred four thousand, one hundred twenty".