113121221 has 4 divisors (see below), whose sum is σ = 113143500. Its totient is φ = 113098944.

The previous prime is 113121209. The next prime is 113121223. The reversal of 113121221 is 122121311.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 70728100 + 42393121 = 8410^2 + 6511^2 .

It is a cyclic number.

It is not a de Polignac number, because 113121221 - 2⁶ = 113121157 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 113121196 and 113121205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (113121223) 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, 605 + ... + 15053.

It is an arithmetic number, because the mean of its divisors is an integer number (28285875).

Almost surely, 2^113121221 is an apocalyptic number.

It is an amenable number.

113121221 is a deficient number, since it is larger than the sum of its proper divisors (22279).

113121221 is an equidigital number, since it uses as much as digits as its factorization.

113121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22278.

The product of its digits is 24, while the sum is 14.

The square root of 113121221 is about 10635.8460406307. The cubic root of 113121221 is about 483.6316281002.

Adding to 113121221 its reverse (122121311), we get a palindrome (235242532).

The spelling of 113121221 in words is "one hundred thirteen million, one hundred twenty-one thousand, two hundred twenty-one".