18114461821 has 2 divisors, whose sum is σ = 18114461822. Its totient is φ = 18114461820.

The previous prime is 18114461749. The next prime is 18114461857. The reversal of 18114461821 is 12816441181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15678545796 + 2435916025 = 125214^2 + 49355^2 .

It is an emirp because it is prime and its reverse (12816441181) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18114461821 - 2¹⁹ = 18113937533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18114461021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9057230910 + 9057230911.

It is an arithmetic number, because the mean of its divisors is an integer number (9057230911).

Almost surely, 2^18114461821 is an apocalyptic number.

It is an amenable number.

18114461821 is a deficient number, since it is larger than the sum of its proper divisors (1).

18114461821 is an equidigital number, since it uses as much as digits as its factorization.

18114461821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12288, while the sum is 37.

The spelling of 18114461821 in words is "eighteen billion, one hundred fourteen million, four hundred sixty-one thousand, eight hundred twenty-one".