121221013 has 2 divisors, whose sum is σ = 121221014. Its totient is φ = 121221012.

The previous prime is 121220993. The next prime is 121221019. The reversal of 121221013 is 310122121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 95394289 + 25826724 = 9767^2 + 5082^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121221013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 121220984 and 121221002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121221019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60610506 + 60610507.

It is an arithmetic number, because the mean of its divisors is an integer number (60610507).

Almost surely, 2^121221013 is an apocalyptic number.

It is an amenable number.

121221013 is a deficient number, since it is larger than the sum of its proper divisors (1).

121221013 is an equidigital number, since it uses as much as digits as its factorization.

121221013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24, while the sum is 13.

The square root of 121221013 is about 11010.0414622289. The cubic root of 121221013 is about 494.9097043065.

Adding to 121221013 its reverse (310122121), we get a palindrome (431343134).

It can be divided in two parts, 12 and 1221013, that added together give a square (1221025 = 1105²).

The spelling of 121221013 in words is "one hundred twenty-one million, two hundred twenty-one thousand, thirteen".