18818771 has 2 divisors, whose sum is σ = 18818772. Its totient is φ = 18818770.

The previous prime is 18818749. The next prime is 18818773. The reversal of 18818771 is 17781881.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 18818771 - 2⁶ = 18818707 is a prime.

It is a super-2 number, since 2×18818771² = 708292283900882, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 18818773, 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 (18818773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9409385 + 9409386.

It is an arithmetic number, because the mean of its divisors is an integer number (9409386).

Almost surely, 2^18818771 is an apocalyptic number.

18818771 is a deficient number, since it is larger than the sum of its proper divisors (1).

18818771 is an equidigital number, since it uses as much as digits as its factorization.

18818771 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25088, while the sum is 41.

The square root of 18818771 is about 4338.0607418523. The cubic root of 18818771 is about 265.9890464142.

The spelling of 18818771 in words is "eighteen million, eight hundred eighteen thousand, seven hundred seventy-one".