21221101111210 has 128 divisors (see below), whose sum is σ = 51326193106944. Its totient is φ = 6100882018560.

The previous prime is 21221101111183. The next prime is 21221101111211. The reversal of 21221101111210 is 1211110112212.

It is not an unprimeable number, because it can be changed into a prime (21221101111211) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 12229527 + ... + 13856533.

It is an arithmetic number, because the mean of its divisors is an integer number (400985883648).

Almost surely, 2^{21221101111210} is an apocalyptic number.

21221101111210 is an abundant number, since it is smaller than the sum of its proper divisors (30105091995734).

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

21221101111210 is a wasteful number, since it uses less digits than its factorization.

21221101111210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1628348.

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

Adding to 21221101111210 its reverse (1211110112212), we get a palindrome (22432211223422).

The spelling of 21221101111210 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred one million, one hundred eleven thousand, two hundred ten".