13678254501221 has 2 divisors, whose sum is σ = 13678254501222. Its totient is φ = 13678254501220.

The previous prime is 13678254501211. The next prime is 13678254501283. The reversal of 13678254501221 is 12210545287631.

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., 11926903996225 + 1751350504996 = 3453535^2 + 1323386^2 .

It is a cyclic number.

It is not a de Polignac number, because 13678254501221 - 2⁶ = 13678254501157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13678254501211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6839127250610 + 6839127250611.

It is an arithmetic number, because the mean of its divisors is an integer number (6839127250611).

Almost surely, 2^{13678254501221} is an apocalyptic number.

It is an amenable number.

13678254501221 is a deficient number, since it is larger than the sum of its proper divisors (1).

13678254501221 is an equidigital number, since it uses as much as digits as its factorization.

13678254501221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 806400, while the sum is 47.

Adding to 13678254501221 its reverse (12210545287631), we get a palindrome (25888799788852).

The spelling of 13678254501221 in words is "thirteen trillion, six hundred seventy-eight billion, two hundred fifty-four million, five hundred one thousand, two hundred twenty-one".