210100121221 has 4 divisors (see below), whose sum is σ = 210245319712. Its totient is φ = 209954922732.

The previous prime is 210100121219. The next prime is 210100121239. The reversal of 210100121221 is 122121001012.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 210100121221 - 2¹ = 210100121219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (210100121251) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72597075 + ... + 72599968.

It is an arithmetic number, because the mean of its divisors is an integer number (52561329928).

Almost surely, 2^210100121221 is an apocalyptic number.

It is an amenable number.

210100121221 is a deficient number, since it is larger than the sum of its proper divisors (145198491).

210100121221 is a wasteful number, since it uses less digits than its factorization.

210100121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145198490.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 210100121221 its reverse (122121001012), we get a palindrome (332221122233).

The spelling of 210100121221 in words is "two hundred ten billion, one hundred million, one hundred twenty-one thousand, two hundred twenty-one".