13121231 has 2 divisors, whose sum is σ = 13121232. Its totient is φ = 13121230.

The previous prime is 13121219. The next prime is 13121243. The reversal of 13121231 is 13212131.

It is a balanced prime because it is at equal distance from previous prime (13121219) and next prime (13121243).

It is an emirp because it is prime and its reverse (13212131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13121231 - 2¹⁸ = 12859087 is a prime.

It is a super-2 number, since 2×13121231² = 344333405910722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13121291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6560615 + 6560616.

It is an arithmetic number, because the mean of its divisors is an integer number (6560616).

Almost surely, 2^13121231 is an apocalyptic number.

13121231 is a deficient number, since it is larger than the sum of its proper divisors (1).

13121231 is an equidigital number, since it uses as much as digits as its factorization.

13121231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36, while the sum is 14.

The square root of 13121231 is about 3622.3239777800. The cubic root of 13121231 is about 235.8621178210.

Adding to 13121231 its reverse (13212131), we get a palindrome (26333362).

It can be divided in two parts, 131 and 21231, that multiplied together give a triangular number (2781261 = T₂₃₅₈).

The spelling of 13121231 in words is "thirteen million, one hundred twenty-one thousand, two hundred thirty-one".