18875789 has 4 divisors (see below), whose sum is σ = 19062780. Its totient is φ = 18688800.

The previous prime is 18875771. The next prime is 18875803. The reversal of 18875789 is 98757881.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98757881 = 419 ⋅235699.

It can be written as a sum of positive squares in 2 ways, for example, as 9815689 + 9060100 = 3133^2 + 3010^2 .

It is a cyclic number.

It is not a de Polignac number, because 18875789 - 2²⁰ = 17827213 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 18875789.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18875749) 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, 93344 + ... + 93545.

It is an arithmetic number, because the mean of its divisors is an integer number (4765695).

Almost surely, 2^18875789 is an apocalyptic number.

It is an amenable number.

18875789 is a deficient number, since it is larger than the sum of its proper divisors (186991).

18875789 is a wasteful number, since it uses less digits than its factorization.

18875789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186990.

The product of its digits is 1128960, while the sum is 53.

The square root of 18875789 is about 4344.6276019931. The cubic root of 18875789 is about 266.2574109482.

The spelling of 18875789 in words is "eighteen million, eight hundred seventy-five thousand, seven hundred eighty-nine".