121331221 has 4 divisors (see below), whose sum is σ = 132361344. Its totient is φ = 110301100.

The previous prime is 121331213. The next prime is 121331239. The reversal of 121331221 is 122133121.

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 not a de Polignac number, because 121331221 - 2³ = 121331213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121331195 and 121331204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121331921) 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, 5515045 + ... + 5515066.

It is an arithmetic number, because the mean of its divisors is an integer number (33090336).

Almost surely, 2^121331221 is an apocalyptic number.

121331221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

121331221 is a deficient number, since it is larger than the sum of its proper divisors (11030123).

121331221 is a wasteful number, since it uses less digits than its factorization.

121331221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11030122.

The product of its digits is 72, while the sum is 16.

The square root of 121331221 is about 11015.0452109830. The cubic root of 121331221 is about 495.0596411489.

Adding to 121331221 its reverse (122133121), we get a palindrome (243464342).

The spelling of 121331221 in words is "one hundred twenty-one million, three hundred thirty-one thousand, two hundred twenty-one".