18378823 has 2 divisors, whose sum is σ = 18378824. Its totient is φ = 18378822.

The previous prime is 18378821. The next prime is 18378827. The reversal of 18378823 is 32887381.

It is a weak prime.

It is an emirp because it is prime and its reverse (32887381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18378823 - 2¹ = 18378821 is a prime.

It is a super-2 number, since 2×18378823² = 675562269730658, which contains 22 as substring.

Together with 18378821, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18378821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9189411 + 9189412.

It is an arithmetic number, because the mean of its divisors is an integer number (9189412).

Almost surely, 2^18378823 is an apocalyptic number.

18378823 is a deficient number, since it is larger than the sum of its proper divisors (1).

18378823 is an equidigital number, since it uses as much as digits as its factorization.

18378823 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64512, while the sum is 40.

The square root of 18378823 is about 4287.0529504544. The cubic root of 18378823 is about 263.8999037044.

The spelling of 18378823 in words is "eighteen million, three hundred seventy-eight thousand, eight hundred twenty-three".