21002231200 has 72 divisors (see below), whose sum is σ = 51496039980. Its totient is φ = 8364134400.

The previous prime is 21002231149. The next prime is 21002231209. The reversal of 21002231200 is 213220012.

It can be written as a sum of positive squares in 6 ways, for example, as 15943607824 + 5058623376 = 126268^2 + 71124^2 .

It is not an unprimeable number, because it can be changed into a prime (21002231209) 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, 125880 + ... + 240520.

Almost surely, 2^21002231200 is an apocalyptic number.

21002231200 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 21002231200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25748019990).

21002231200 is an abundant number, since it is smaller than the sum of its proper divisors (30493808780).

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

21002231200 is a wasteful number, since it uses less digits than its factorization.

21002231200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114890 (or 114877 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

Adding to 21002231200 its reverse (213220012), we get a palindrome (21215451212).

The spelling of 21002231200 in words is "twenty-one billion, two million, two hundred thirty-one thousand, two hundred".