18923838 has 16 divisors (see below), whose sum is σ = 38090640. Its totient is φ = 6267456.

The previous prime is 18923833. The next prime is 18923851. The reversal of 18923838 is 83832981.

It is a super-2 number, since 2×18923838² = 716223289300488, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 18923838.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18923831) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9103 + ... + 10986.

It is an arithmetic number, because the mean of its divisors is an integer number (2380665).

Almost surely, 2^18923838 is an apocalyptic number.

18923838 is an abundant number, since it is smaller than the sum of its proper divisors (19166802).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18923838 is a wasteful number, since it uses less digits than its factorization.

18923838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20251.

The product of its digits is 82944, while the sum is 42.

The square root of 18923838 is about 4350.1537903849. The cubic root of 18923838 is about 266.4831421270.

The spelling of 18923838 in words is "eighteen million, nine hundred twenty-three thousand, eight hundred thirty-eight".