18343890 has 24 divisors (see below), whose sum is σ = 47694348. Its totient is φ = 4891680.

The previous prime is 18343861. The next prime is 18343891. The reversal of 18343890 is 9834381.

18343890 is nontrivially palindromic in base 12.

It can be written as a sum of positive squares in 2 ways, for example, as 18122049 + 221841 = 4257^2 + 471^2 .

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

It is not an unprimeable number, because it can be changed into a prime (18343891) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 101821 + ... + 102000.

Almost surely, 2^18343890 is an apocalyptic number.

18343890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18343890 is an abundant number, since it is smaller than the sum of its proper divisors (29350458).

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

18343890 is a wasteful number, since it uses less digits than its factorization.

18343890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203834 (or 203831 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 18343890 is about 4282.9767685571. The cubic root of 18343890 is about 263.7325977003.

The spelling of 18343890 in words is "eighteen million, three hundred forty-three thousand, eight hundred ninety".