12977477921 has 2 divisors, whose sum is σ = 12977477922. Its totient is φ = 12977477920.

The previous prime is 12977477839. The next prime is 12977477923.

12977477921 is nontrivially palindromic in base 10.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12235678225 + 741799696 = 110615^2 + 27236^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 12977477921 - 2¹⁴ = 12977461537 is a prime.

Together with 12977477923, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12977477923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6488738960 + 6488738961.

It is an arithmetic number, because the mean of its divisors is an integer number (6488738961).

Almost surely, 2^12977477921 is an apocalyptic number.

It is an amenable number.

12977477921 is a deficient number, since it is larger than the sum of its proper divisors (1).

12977477921 is an equidigital number, since it uses as much as digits as its factorization.

12977477921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3111696, while the sum is 56.

The spelling of 12977477921 in words is "twelve billion, nine hundred seventy-seven million, four hundred seventy-seven thousand, nine hundred twenty-one".