18749999 has 4 divisors (see below), whose sum is σ = 18763920. Its totient is φ = 18736080.

The previous prime is 18749993. The next prime is 18750001. The reversal of 18749999 is 99994781.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99994781 = 4243 ⋅23567.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18749999 is a prime.

It is a Duffinian number.

18749999 is a modest number, since divided by 9999 gives 1874 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18749993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4694 + ... + 7715.

It is an arithmetic number, because the mean of its divisors is an integer number (4690980).

Almost surely, 2^18749999 is an apocalyptic number.

18749999 is a deficient number, since it is larger than the sum of its proper divisors (13921).

18749999 is a wasteful number, since it uses less digits than its factorization.

18749999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13920.

The product of its digits is 1469664, while the sum is 56.

The square root of 18749999 is about 4330.1269034521. The cubic root of 18749999 is about 265.6646375727.

The spelling of 18749999 in words is "eighteen million, seven hundred forty-nine thousand, nine hundred ninety-nine".