21220220210 has 64 divisors (see below), whose sum is σ = 45733330944. Its totient is φ = 6931320000.

The previous prime is 21220220173. The next prime is 21220220237. The reversal of 21220220210 is 1202202212.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 377855 + ... + 430365.

It is an arithmetic number, because the mean of its divisors is an integer number (714583296).

Almost surely, 2^21220220210 is an apocalyptic number.

21220220210 is an abundant number, since it is smaller than the sum of its proper divisors (24513110734).

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

21220220210 is a wasteful number, since it uses less digits than its factorization.

21220220210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52799.

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 21220220210 its reverse (1202202212), we get a palindrome (22422422422).

It can be divided in two parts, 212202202 and 10, that added together give a palindrome (212202212).

The spelling of 21220220210 in words is "twenty-one billion, two hundred twenty million, two hundred twenty thousand, two hundred ten".