21234032400 has 480 divisors, whose sum is σ = 82808985600. Its totient is φ = 4640401920.

The previous prime is 21234032399. The next prime is 21234032431. The reversal of 21234032400 is 423043212.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

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 95 ways as a sum of consecutive naturals, for example, 9465679 + ... + 9467921.

It is an arithmetic number, because the mean of its divisors is an integer number (172518720).

Almost surely, 2^21234032400 is an apocalyptic number.

21234032400 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 21234032400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41404492800).

21234032400 is an abundant number, since it is smaller than the sum of its proper divisors (61574953200).

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

21234032400 is a wasteful number, since it uses less digits than its factorization.

21234032400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2308 (or 2283 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 21.

Adding to 21234032400 its reverse (423043212), we get a palindrome (21657075612).

The spelling of 21234032400 in words is "twenty-one billion, two hundred thirty-four million, thirty-two thousand, four hundred".