18920869 has 8 divisors (see below), whose sum is σ = 20704608. Its totient is φ = 17147760.

The previous prime is 18920857. The next prime is 18920873. The reversal of 18920869 is 96802981.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18920869 is a prime.

It is a super-2 number, since 2×18920869² = 715998567430322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18920809) 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 7 ways as a sum of consecutive naturals, for example, 1339 + ... + 6295.

It is an arithmetic number, because the mean of its divisors is an integer number (2588076).

Almost surely, 2^18920869 is an apocalyptic number.

It is an amenable number.

18920869 is a deficient number, since it is larger than the sum of its proper divisors (1783739).

18920869 is a wasteful number, since it uses less digits than its factorization.

18920869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5315.

The product of its (nonzero) digits is 62208, while the sum is 43.

The square root of 18920869 is about 4349.8125246957. The cubic root of 18920869 is about 266.4692050348.

The spelling of 18920869 in words is "eighteen million, nine hundred twenty thousand, eight hundred sixty-nine".