11981673416021 has 2 divisors, whose sum is σ = 11981673416022. Its totient is φ = 11981673416020.

The previous prime is 11981673415997. The next prime is 11981673416029. The reversal of 11981673416021 is 12061437618911.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11978624830225 + 3048585796 = 3461015^2 + 55214^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11981673416021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11981673416029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5990836708010 + 5990836708011.

It is an arithmetic number, because the mean of its divisors is an integer number (5990836708011).

Almost surely, 2^{11981673416021} is an apocalyptic number.

It is an amenable number.

11981673416021 is a deficient number, since it is larger than the sum of its proper divisors (1).

11981673416021 is an equidigital number, since it uses as much as digits as its factorization.

11981673416021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 435456, while the sum is 50.

The spelling of 11981673416021 in words is "eleven trillion, nine hundred eighty-one billion, six hundred seventy-three million, four hundred sixteen thousand, twenty-one".