18890423 has 4 divisors (see below), whose sum is σ = 18914040. Its totient is φ = 18866808.

The previous prime is 18890413. The next prime is 18890441. The reversal of 18890423 is 32409881.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32409881 = 7 ⋅4629983.

It is a cyclic number.

It is not a de Polignac number, because 18890423 - 2⁶ = 18890359 is a prime.

It is a super-2 number, since 2×18890423² = 713696162237858, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18890413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10565 + ... + 12222.

It is an arithmetic number, because the mean of its divisors is an integer number (4728510).

Almost surely, 2^18890423 is an apocalyptic number.

18890423 is a deficient number, since it is larger than the sum of its proper divisors (23617).

18890423 is an equidigital number, since it uses as much as digits as its factorization.

18890423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23616.

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 18890423 is about 4346.3114246450. The cubic root of 18890423 is about 266.3262010872.

The spelling of 18890423 in words is "eighteen million, eight hundred ninety thousand, four hundred twenty-three".