13870121 has 2 divisors, whose sum is σ = 13870122. Its totient is φ = 13870120.

The previous prime is 13870111. The next prime is 13870151. The reversal of 13870121 is 12107831.

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., 12524521 + 1345600 = 3539^2 + 1160^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13870121 is a prime.

It is not a weakly prime, because it can be changed into another prime (13870111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6935060 + 6935061.

It is an arithmetic number, because the mean of its divisors is an integer number (6935061).

Almost surely, 2^13870121 is an apocalyptic number.

It is an amenable number.

13870121 is a deficient number, since it is larger than the sum of its proper divisors (1).

13870121 is an equidigital number, since it uses as much as digits as its factorization.

13870121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 336, while the sum is 23.

The square root of 13870121 is about 3724.2611347756. The cubic root of 13870121 is about 240.2666076603.

Adding to 13870121 its reverse (12107831), we get a palindrome (25977952).

The spelling of 13870121 in words is "thirteen million, eight hundred seventy thousand, one hundred twenty-one".