21220121020210 has 96 divisors (see below), whose sum is σ = 47105249200128. Its totient is φ = 6850486016640.

The previous prime is 21220121020103. The next prime is 21220121020211. The reversal of 21220121020210 is 1202012102212.

It is a happy number.

It is a super-2 number, since 2×21220121020210² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21220121020211) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 18316074 + ... + 19440133.

It is an arithmetic number, because the mean of its divisors is an integer number (490679679168).

Almost surely, 2^{21220121020210} is an apocalyptic number.

21220121020210 is an abundant number, since it is smaller than the sum of its proper divisors (25885128179918).

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

21220121020210 is a wasteful number, since it uses less digits than its factorization.

21220121020210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37756296 (or 37756289 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21220121020210 its reverse (1202012102212), we get a palindrome (22422133122422).

The spelling of 21220121020210 in words is "twenty-one trillion, two hundred twenty billion, one hundred twenty-one million, twenty thousand, two hundred ten".