13977978841 has 2 divisors, whose sum is σ = 13977978842. Its totient is φ = 13977978840.

The previous prime is 13977978827. The next prime is 13977978893. The reversal of 13977978841 is 14887977931.

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., 13711473216 + 266505625 = 117096^2 + 16325^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13977978841 is a prime.

It is not a weakly prime, because it can be changed into another prime (13977978241) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6988989420 + 6988989421.

It is an arithmetic number, because the mean of its divisors is an integer number (6988989421).

Almost surely, 2^13977978841 is an apocalyptic number.

It is an amenable number.

13977978841 is a deficient number, since it is larger than the sum of its proper divisors (1).

13977978841 is an equidigital number, since it uses as much as digits as its factorization.

13977978841 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21337344, while the sum is 64.

The spelling of 13977978841 in words is "thirteen billion, nine hundred seventy-seven million, nine hundred seventy-eight thousand, eight hundred forty-one".