21220101210 has 384 divisors, whose sum is σ = 66487163904. Its totient is φ = 4284887040.

The previous prime is 21220101209. The next prime is 21220101211. The reversal of 21220101210 is 1210102212.

It is an interprime number because it is at equal distance from previous prime (21220101209) and next prime (21220101211).

It is not an unprimeable number, because it can be changed into a prime (21220101211) by changing a digit.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 130184589 + ... + 130184751.

It is an arithmetic number, because the mean of its divisors is an integer number (173143656).

Almost surely, 2^21220101210 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21220101210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33243581952).

21220101210 is an abundant number, since it is smaller than the sum of its proper divisors (45267062694).

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

21220101210 is a wasteful number, since it uses less digits than its factorization.

21220101210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378 (or 371 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21220101210 its reverse (1210102212), we get a palindrome (22430203422).

The spelling of 21220101210 in words is "twenty-one billion, two hundred twenty million, one hundred one thousand, two hundred ten".