221212200100021 has 8 divisors (see below), whose sum is σ = 240541421469440. Its totient is φ = 202213392771312.

The previous prime is 221212200100009. The next prime is 221212200100037. The reversal of 221212200100021 is 120001002212122.

It is a happy number.

221212200100021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 221212200100021 - 2²⁵ = 221212166545589 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 221212200099968 and 221212200100004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221212200100061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82603508781 + ... + 82603511458.

It is an arithmetic number, because the mean of its divisors is an integer number (30067677683680).

Almost surely, 2^{221212200100021} is an apocalyptic number.

It is an amenable number.

221212200100021 is a deficient number, since it is larger than the sum of its proper divisors (19329221369419).

221212200100021 is a wasteful number, since it uses less digits than its factorization.

221212200100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165207020355.

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

Adding to 221212200100021 its reverse (120001002212122), we get a palindrome (341213202312143).

The spelling of 221212200100021 in words is "two hundred twenty-one trillion, two hundred twelve billion, two hundred million, one hundred thousand, twenty-one".