10121212221221 has 4 divisors (see below), whose sum is σ = 10122213241344. Its totient is φ = 10120211201100.

The previous prime is 10121212221193. The next prime is 10121212221227. The reversal of 10121212221221 is 12212221212101.

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 10121212221221 - 2⁴² = 5723165710117 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10121212221193 and 10121212221202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10121212221227) 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, 500494895 + ... + 500515116.

It is an arithmetic number, because the mean of its divisors is an integer number (2530553310336).

Almost surely, 2^{10121212221221} is an apocalyptic number.

It is an amenable number.

10121212221221 is a deficient number, since it is larger than the sum of its proper divisors (1001020123).

10121212221221 is a wasteful number, since it uses less digits than its factorization.

10121212221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1001020122.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 10121212221221 its reverse (12212221212101), we get a palindrome (22333433433322).

The spelling of 10121212221221 in words is "ten trillion, one hundred twenty-one billion, two hundred twelve million, two hundred twenty-one thousand, two hundred twenty-one".