11810278021 has 2 divisors, whose sum is σ = 11810278022. Its totient is φ = 11810278020.

The previous prime is 11810278013. The next prime is 11810278049. The reversal of 11810278021 is 12087201811.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11774637121 + 35640900 = 108511^2 + 5970^2 .

It is a cyclic number.

It is not a de Polignac number, because 11810278021 - 2³ = 11810278013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11810278061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5905139010 + 5905139011.

It is an arithmetic number, because the mean of its divisors is an integer number (5905139011).

Almost surely, 2^11810278021 is an apocalyptic number.

It is an amenable number.

11810278021 is a deficient number, since it is larger than the sum of its proper divisors (1).

11810278021 is an equidigital number, since it uses as much as digits as its factorization.

11810278021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1792, while the sum is 31.

Adding to 11810278021 its reverse (12087201811), we get a palindrome (23897479832).

The spelling of 11810278021 in words is "eleven billion, eight hundred ten million, two hundred seventy-eight thousand, twenty-one".