2012111221 has 4 divisors (see below), whose sum is σ = 2018581344. Its totient is φ = 2005641100.

The previous prime is 2012111209. The next prime is 2012111249. The reversal of 2012111221 is 1221112102.

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 a de Polignac number, because none of the positive numbers 2^k-2012111221 is a prime.

It is a super-2 number, since 2×2012111221² = 8097183131348221682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2012151221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3234595 + ... + 3235216.

It is an arithmetic number, because the mean of its divisors is an integer number (504645336).

Almost surely, 2^2012111221 is an apocalyptic number.

It is an amenable number.

2012111221 is a deficient number, since it is larger than the sum of its proper divisors (6470123).

2012111221 is an equidigital number, since it uses as much as digits as its factorization.

2012111221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6470122.

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 2012111221 is about 44856.5627416992. The cubic root of 2012111221 is about 1262.4591306052.

Adding to 2012111221 its reverse (1221112102), we get a palindrome (3233223323).

The spelling of 2012111221 in words is "two billion, twelve million, one hundred eleven thousand, two hundred twenty-one".