21124201320 has 96 divisors (see below), whose sum is σ = 70509202920. Its totient is φ = 5480870400.

The previous prime is 21124201313. The next prime is 21124201337. The reversal of 21124201320 is 2310242112.

It is a happy number.

21124201320 is a `hidden beast` number, since 2 + 112 + 420 + 132 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 20799985284 + 324216036 = 144222^2 + 18006^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21124201293 and 21124201302.

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 23 ways as a sum of consecutive naturals, for example, 779631 + ... + 806270.

Almost surely, 2^21124201320 is an apocalyptic number.

21124201320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21124201320 is an abundant number, since it is smaller than the sum of its proper divisors (49385001600).

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

21124201320 is a wasteful number, since it uses less digits than its factorization.

21124201320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1585955 (or 1585948 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21124201320 its reverse (2310242112), we get a palindrome (23434443432).

The spelling of 21124201320 in words is "twenty-one billion, one hundred twenty-four million, two hundred one thousand, three hundred twenty".