211220212121 has 8 divisors (see below), whose sum is σ = 213120129024. Its totient is φ = 209320834240.

The previous prime is 211220212117. The next prime is 211220212127. The reversal of 211220212121 is 121212022112.

211220212121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 211220212121 - 2² = 211220212117 is a prime.

It is a super-2 number, since 2×211220212121² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 211220212121.

It is not an unprimeable number, because it can be changed into a prime (211220212127) 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 7 ways as a sum of consecutive naturals, for example, 674216 + ... + 936486.

It is an arithmetic number, because the mean of its divisors is an integer number (26640016128).

Almost surely, 2^211220212121 is an apocalyptic number.

It is an amenable number.

211220212121 is a deficient number, since it is larger than the sum of its proper divisors (1899916903).

211220212121 is a wasteful number, since it uses less digits than its factorization.

211220212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269511.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 211220212121 its reverse (121212022112), we get a palindrome (332432234233).

The spelling of 211220212121 in words is "two hundred eleven billion, two hundred twenty million, two hundred twelve thousand, one hundred twenty-one".