21220100121 has 8 divisors (see below), whose sum is σ = 30865600224. Its totient is φ = 12860666720.

The previous prime is 21220100051. The next prime is 21220100123. The reversal of 21220100121 is 12100102212.

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

It is not a de Polignac number, because 21220100121 - 2⁹ = 21220099609 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21220100097 and 21220100106.

It is not an unprimeable number, because it can be changed into a prime (21220100123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 321516636 + ... + 321516701.

It is an arithmetic number, because the mean of its divisors is an integer number (3858200028).

Almost surely, 2^21220100121 is an apocalyptic number.

It is an amenable number.

21220100121 is a deficient number, since it is larger than the sum of its proper divisors (9645500103).

21220100121 is a wasteful number, since it uses less digits than its factorization.

21220100121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 643033351.

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

Adding to 21220100121 its reverse (12100102212), we get a palindrome (33320202333).

The spelling of 21220100121 in words is "twenty-one billion, two hundred twenty million, one hundred thousand, one hundred twenty-one".