21320030400 has 84 divisors (see below), whose sum is σ = 69947482152. Its totient is φ = 5685340160.

The previous prime is 21320030393. The next prime is 21320030401. The reversal of 21320030400 is 403002312.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21320030400.

It is not an unprimeable number, because it can be changed into a prime (21320030401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2216037 + ... + 2225636.

Almost surely, 2^21320030400 is an apocalyptic number.

21320030400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21320030400 is an abundant number, since it is smaller than the sum of its proper divisors (48627451752).

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

21320030400 is a wasteful number, since it uses less digits than its factorization.

21320030400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4441698 (or 4441683 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

Adding to 21320030400 its reverse (403002312), we get a palindrome (21723032712).

The spelling of 21320030400 in words is "twenty-one billion, three hundred twenty million, thirty thousand, four hundred".