18945719 has 4 divisors (see below), whose sum is σ = 20403096. Its totient is φ = 17488344.

The previous prime is 18945691. The next prime is 18945727. The reversal of 18945719 is 91754981.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18945719 - 2¹² = 18941623 is a prime.

It is a super-2 number, since 2×18945719² = 717880536853922, which contains 22 as substring.

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 18945719.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18945779) 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, 728669 + ... + 728694.

It is an arithmetic number, because the mean of its divisors is an integer number (5100774).

Almost surely, 2^18945719 is an apocalyptic number.

18945719 is a deficient number, since it is larger than the sum of its proper divisors (1457377).

18945719 is a wasteful number, since it uses less digits than its factorization.

18945719 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1457376.

The product of its digits is 90720, while the sum is 44.

The square root of 18945719 is about 4352.6680323682. The cubic root of 18945719 is about 266.5858110767.

The spelling of 18945719 in words is "eighteen million, nine hundred forty-five thousand, seven hundred nineteen".