2221231521 has 16 divisors (see below), whose sum is σ = 3073213440. Its totient is φ = 1426005840.

The previous prime is 2221231489. The next prime is 2221231531. The reversal of 2221231521 is 1251321222.

It is not a de Polignac number, because 2221231521 - 2⁵ = 2221231489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2221231531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 112101 + ... + 130418.

It is an arithmetic number, because the mean of its divisors is an integer number (192075840).

Almost surely, 2^2221231521 is an apocalyptic number.

It is an amenable number.

2221231521 is a deficient number, since it is larger than the sum of its proper divisors (851981919).

2221231521 is a wasteful number, since it uses less digits than its factorization.

2221231521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242636.

The product of its digits is 480, while the sum is 21.

The square root of 2221231521 is about 47129.9429344021. The cubic root of 2221231521 is about 1304.7619283566.

Adding to 2221231521 its reverse (1251321222), we get a palindrome (3472552743).

The spelling of 2221231521 in words is "two billion, two hundred twenty-one million, two hundred thirty-one thousand, five hundred twenty-one".