1376881211921 has 2 divisors, whose sum is σ = 1376881211922. Its totient is φ = 1376881211920.

The previous prime is 1376881211801. The next prime is 1376881211957. The reversal of 1376881211921 is 1291121886731.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1094197589521 + 282683622400 = 1046039^2 + 531680^2 .

It is a cyclic number.

It is not a de Polignac number, because 1376881211921 - 2³⁰ = 1375807470097 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1376881211921.

It is not a weakly prime, because it can be changed into another prime (1376881211621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 688440605960 + 688440605961.

It is an arithmetic number, because the mean of its divisors is an integer number (688440605961).

Almost surely, 2^{1376881211921} is an apocalyptic number.

It is an amenable number.

1376881211921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1376881211921 is an equidigital number, since it uses as much as digits as its factorization.

1376881211921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 290304, while the sum is 50.

The spelling of 1376881211921 in words is "one trillion, three hundred seventy-six billion, eight hundred eighty-one million, two hundred eleven thousand, nine hundred twenty-one".