18435881 has 2 divisors, whose sum is σ = 18435882. Its totient is φ = 18435880.

The previous prime is 18435869. The next prime is 18435883. The reversal of 18435881 is 18853481.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13104400 + 5331481 = 3620^2 + 2309^2 .

It is a cyclic number.

It is not a de Polignac number, because 18435881 - 2⁶ = 18435817 is a prime.

It is a super-2 number, since 2×18435881² = 679763416492322, which contains 22 as substring.

Together with 18435883, 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 (18435883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9217940 + 9217941.

It is an arithmetic number, because the mean of its divisors is an integer number (9217941).

Almost surely, 2^18435881 is an apocalyptic number.

It is an amenable number.

18435881 is a deficient number, since it is larger than the sum of its proper divisors (1).

18435881 is an equidigital number, since it uses as much as digits as its factorization.

18435881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30720, while the sum is 38.

The square root of 18435881 is about 4293.7024815420. The cubic root of 18435881 is about 264.1727185116.

The spelling of 18435881 in words is "eighteen million, four hundred thirty-five thousand, eight hundred eighty-one".