2221212021 has 32 divisors (see below), whose sum is σ = 3426167808. Its totient is φ = 1253767680.

The previous prime is 2221212013. The next prime is 2221212041. The reversal of 2221212021 is 1202121222.

It is not a de Polignac number, because 2221212021 - 2³ = 2221212013 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2221212011) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1977366 + ... + 1978488.

It is an arithmetic number, because the mean of its divisors is an integer number (107067744).

Almost surely, 2^2221212021 is an apocalyptic number.

2221212021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2221212021 is a deficient number, since it is larger than the sum of its proper divisors (1204955787).

2221212021 is a wasteful number, since it uses less digits than its factorization.

2221212021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2201.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 2221212021 is about 47129.7360590954. The cubic root of 2221212021 is about 1304.7581102146.

Adding to 2221212021 its reverse (1202121222), we get a palindrome (3423333243).

The spelling of 2221212021 in words is "two billion, two hundred twenty-one million, two hundred twelve thousand, twenty-one".