18942823 has 4 divisors (see below), whose sum is σ = 19766448. Its totient is φ = 18119200.

The previous prime is 18942809. The next prime is 18942851. The reversal of 18942823 is 32824981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32824981 = 7 ⋅4689283.

It is a cyclic number.

It is not a de Polignac number, because 18942823 - 2⁹ = 18942311 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18942883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 411778 + ... + 411823.

It is an arithmetic number, because the mean of its divisors is an integer number (4941612).

Almost surely, 2^18942823 is an apocalyptic number.

18942823 is a deficient number, since it is larger than the sum of its proper divisors (823625).

18942823 is an equidigital number, since it uses as much as digits as its factorization.

18942823 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 823624.

The product of its digits is 27648, while the sum is 37.

The square root of 18942823 is about 4352.3353501310. The cubic root of 18942823 is about 266.5722271486.

It can be divided in two parts, 18 and 942823, that added together give a square (942841 = 971²).

The spelling of 18942823 in words is "eighteen million, nine hundred forty-two thousand, eight hundred twenty-three".