21221200210 has 32 divisors (see below), whose sum is σ = 44078890752. Its totient is φ = 7205198400.

The previous prime is 21221200207. The next prime is 21221200211. The reversal of 21221200210 is 1200212212.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21221200211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1464441 + ... + 1478860.

It is an arithmetic number, because the mean of its divisors is an integer number (1377465336).

Almost surely, 2^21221200210 is an apocalyptic number.

21221200210 is an abundant number, since it is smaller than the sum of its proper divisors (22857690542).

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

21221200210 is a wasteful number, since it uses less digits than its factorization.

21221200210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2943418.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21221200210 its reverse (1200212212), we get a palindrome (22421412422).

The spelling of 21221200210 in words is "twenty-one billion, two hundred twenty-one million, two hundred thousand, two hundred ten".