2211236721 has 12 divisors (see below), whose sum is σ = 3332878848. Its totient is φ = 1410063864.

The previous prime is 2211236717. The next prime is 2211236743. The reversal of 2211236721 is 1276321122.

2211236721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2211236721 - 2² = 2211236717 is a prime.

It is a super-3 number, since 3×2211236721³ (a number of 29 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (2211236761) 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, 5340945 + ... + 5341358.

It is an arithmetic number, because the mean of its divisors is an integer number (277739904).

Almost surely, 2^2211236721 is an apocalyptic number.

It is an amenable number.

2211236721 is a deficient number, since it is larger than the sum of its proper divisors (1121642127).

2211236721 is a wasteful number, since it uses less digits than its factorization.

2211236721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10682332 (or 10682329 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 2211236721 is about 47023.7888839255. The cubic root of 2211236721 is about 1302.8019880801.

Adding to 2211236721 its reverse (1276321122), we get a palindrome (3487557843).

The spelling of 2211236721 in words is "two billion, two hundred eleven million, two hundred thirty-six thousand, seven hundred twenty-one".