21223251200 has 108 divisors (see below), whose sum is σ = 53052586188. Its totient is φ = 8404992000.

The previous prime is 21223251191. The next prime is 21223251241. The reversal of 21223251200 is 215232212.

It can be written as a sum of positive squares in 6 ways, for example, as 1045616896 + 20177634304 = 32336^2 + 142048^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 629984 + ... + 662816.

Almost surely, 2^21223251200 is an apocalyptic number.

21223251200 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 21223251200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26526293094).

21223251200 is an abundant number, since it is smaller than the sum of its proper divisors (31829334988).

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

21223251200 is a wasteful number, since it uses less digits than its factorization.

21223251200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32960 (or 32941 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

Adding to 21223251200 its reverse (215232212), we get a palindrome (21438483412).

The spelling of 21223251200 in words is "twenty-one billion, two hundred twenty-three million, two hundred fifty-one thousand, two hundred".