1121512221 has 24 divisors (see below), whose sum is σ = 1708281120. Its totient is φ = 707053536.

The previous prime is 1121512211. The next prime is 1121512289. The reversal of 1121512221 is 1222151211.

1121512221 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1121512221 - 2¹⁰ = 1121511197 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1121512194 and 1121512203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1121512211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 94791 + ... + 105963.

It is an arithmetic number, because the mean of its divisors is an integer number (71178380).

Almost surely, 2^1121512221 is an apocalyptic number.

It is an amenable number.

1121512221 is a deficient number, since it is larger than the sum of its proper divisors (586768899).

1121512221 is a wasteful number, since it uses less digits than its factorization.

1121512221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11785 (or 11782 counting only the distinct ones).

The product of its digits is 80, while the sum is 18.

The square root of 1121512221 is about 33488.9865627493. The cubic root of 1121512221 is about 1038.9660029456.

Adding to 1121512221 its reverse (1222151211), we get a palindrome (2343663432).

It can be divided in two parts, 11215 and 12221, that added together give a triangular number (23436 = T₂₁₆).

The spelling of 1121512221 in words is "one billion, one hundred twenty-one million, five hundred twelve thousand, two hundred twenty-one".