121223813 has 2 divisors, whose sum is σ = 121223814. Its totient is φ = 121223812.

The previous prime is 121223807. The next prime is 121223827. The reversal of 121223813 is 318322121.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 108847489 + 12376324 = 10433^2 + 3518^2 .

It is a cyclic number.

It is not a de Polignac number, because 121223813 - 2⁶ = 121223749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121223833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60611906 + 60611907.

It is an arithmetic number, because the mean of its divisors is an integer number (60611907).

Almost surely, 2^121223813 is an apocalyptic number.

It is an amenable number.

121223813 is a deficient number, since it is larger than the sum of its proper divisors (1).

121223813 is an equidigital number, since it uses as much as digits as its factorization.

121223813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 576, while the sum is 23.

The square root of 121223813 is about 11010.1686181457. The cubic root of 121223813 is about 494.9135148023.

Adding to 121223813 its reverse (318322121), we get a palindrome (439545934).

The spelling of 121223813 in words is "one hundred twenty-one million, two hundred twenty-three thousand, eight hundred thirteen".