18818797 has 4 divisors (see below), whose sum is σ = 19809280. Its totient is φ = 17828316.

The previous prime is 18818791. The next prime is 18818809. The reversal of 18818797 is 79781881.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18818797 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 18818797.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18818791) 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, 495213 + ... + 495250.

It is an arithmetic number, because the mean of its divisors is an integer number (4952320).

Almost surely, 2^18818797 is an apocalyptic number.

It is an amenable number.

18818797 is a deficient number, since it is larger than the sum of its proper divisors (990483).

18818797 is an equidigital number, since it uses as much as digits as its factorization.

18818797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 990482.

The product of its digits is 225792, while the sum is 49.

The square root of 18818797 is about 4338.0637385820. The cubic root of 18818797 is about 265.9891689109.

The spelling of 18818797 in words is "eighteen million, eight hundred eighteen thousand, seven hundred ninety-seven".