20100212101221 has 24 divisors (see below), whose sum is σ = 31526129525760. Its totient is φ = 11356781147712.

The previous prime is 20100212101139. The next prime is 20100212101259. The reversal of 20100212101221 is 12210121200102.

It is not a de Polignac number, because 20100212101221 - 2⁷ = 20100212101093 is a prime.

It is a super-2 number, since 2×20100212101221² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20100212101221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20100212101271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 768167461 + ... + 768193626.

It is an arithmetic number, because the mean of its divisors is an integer number (1313588730240).

Almost surely, 2^{20100212101221} is an apocalyptic number.

20100212101221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20100212101221 is a deficient number, since it is larger than the sum of its proper divisors (11425917424539).

20100212101221 is a wasteful number, since it uses less digits than its factorization.

20100212101221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1536361193 (or 1536361186 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 20100212101221 its reverse (12210121200102), we get a palindrome (32310333301323).

The spelling of 20100212101221 in words is "twenty trillion, one hundred billion, two hundred twelve million, one hundred one thousand, two hundred twenty-one".