221020100212121 has 16 divisors (see below), whose sum is σ = 253320806716800. Its totient is φ = 188901041269248.

The previous prime is 221020100212117. The next prime is 221020100212139. The reversal of 221020100212121 is 121212001020122.

It is not a de Polignac number, because 221020100212121 - 2² = 221020100212117 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 221020100212121.

It is not an unprimeable number, because it can be changed into a prime (221020100212921) 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, 56188370 + ... + 59993108.

It is an arithmetic number, because the mean of its divisors is an integer number (15832550419800).

Almost surely, 2^{221020100212121} is an apocalyptic number.

It is an amenable number.

221020100212121 is a deficient number, since it is larger than the sum of its proper divisors (32300706504679).

221020100212121 is a wasteful number, since it uses less digits than its factorization.

221020100212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3828608.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 221020100212121 its reverse (121212001020122), we get a palindrome (342232101232243).

The spelling of 221020100212121 in words is "two hundred twenty-one trillion, twenty billion, one hundred million, two hundred twelve thousand, one hundred twenty-one".