20100212221 has 4 divisors (see below), whose sum is σ = 20101852512. Its totient is φ = 20098571932.

The previous prime is 20100212219. The next prime is 20100212267. The reversal of 20100212221 is 12221200102.

It is a happy number.

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 20100212221 - 2¹ = 20100212219 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 (20100212201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 801625 + ... + 826318.

It is an arithmetic number, because the mean of its divisors is an integer number (5025463128).

Almost surely, 2^20100212221 is an apocalyptic number.

It is an amenable number.

20100212221 is a deficient number, since it is larger than the sum of its proper divisors (1640291).

20100212221 is a wasteful number, since it uses less digits than its factorization.

20100212221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1640290.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 20100212221 its reverse (12221200102), we get a palindrome (32321412323).

The spelling of 20100212221 in words is "twenty billion, one hundred million, two hundred twelve thousand, two hundred twenty-one".