13971921361 has 2 divisors, whose sum is σ = 13971921362. Its totient is φ = 13971921360.

The previous prime is 13971921349. The next prime is 13971921437. The reversal of 13971921361 is 16312917931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13967694225 + 4227136 = 118185^2 + 2056^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13971921361 is a prime.

It is not a weakly prime, because it can be changed into another prime (13971921331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6985960680 + 6985960681.

It is an arithmetic number, because the mean of its divisors is an integer number (6985960681).

Almost surely, 2^13971921361 is an apocalyptic number.

It is an amenable number.

13971921361 is a deficient number, since it is larger than the sum of its proper divisors (1).

13971921361 is an equidigital number, since it uses as much as digits as its factorization.

13971921361 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 61236, while the sum is 43.

The spelling of 13971921361 in words is "thirteen billion, nine hundred seventy-one million, nine hundred twenty-one thousand, three hundred sixty-one".