18103997 has 4 divisors (see below), whose sum is σ = 19168956. Its totient is φ = 17039040.

The previous prime is 18103993. The next prime is 18103999. The reversal of 18103997 is 79930181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 79930181 = 1801 ⋅44381.

It can be written as a sum of positive squares in 2 ways, for example, as 15476356 + 2627641 = 3934^2 + 1621^2 .

It is a cyclic number.

It is not a de Polignac number, because 18103997 - 2² = 18103993 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18103997.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18103991) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 532454 + ... + 532487.

It is an arithmetic number, because the mean of its divisors is an integer number (4792239).

Almost surely, 2^18103997 is an apocalyptic number.

18103997 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

18103997 is a deficient number, since it is larger than the sum of its proper divisors (1064959).

18103997 is a wasteful number, since it uses less digits than its factorization.

18103997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1064958.

The product of its (nonzero) digits is 13608, while the sum is 38.

The square root of 18103997 is about 4254.8791992253. The cubic root of 18103997 is about 262.5778913220.

The spelling of 18103997 in words is "eighteen million, one hundred three thousand, nine hundred ninety-seven".