211212121021 has 12 divisors (see below), whose sum is σ = 244764223200. Its totient is φ = 180716250560.

The previous prime is 211212120991. The next prime is 211212121067. The reversal of 211212121021 is 120121212112.

It is not a de Polignac number, because 211212121021 - 2²³ = 211203732413 is a prime.

It is a super-2 number, since 2×211212121021² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 211212120986 and 211212121004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211212121091) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 33216721 + ... + 33223078.

It is an arithmetic number, because the mean of its divisors is an integer number (20397018600).

Almost surely, 2^211212121021 is an apocalyptic number.

It is an amenable number.

211212121021 is a deficient number, since it is larger than the sum of its proper divisors (33552102179).

211212121021 is a wasteful number, since it uses less digits than its factorization.

211212121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66439844 (or 66439827 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 211212121021 its reverse (120121212112), we get a palindrome (331333333133).

It can be divided in two parts, 211212 and 121021, that added together give a palindrome (332233).

The spelling of 211212121021 in words is "two hundred eleven billion, two hundred twelve million, one hundred twenty-one thousand, twenty-one".