18983947 has 4 divisors (see below), whose sum is σ = 19809360. Its totient is φ = 18158536.

The previous prime is 18983929. The next prime is 18983957. The reversal of 18983947 is 74938981.

It is a happy number.

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 18983947 - 2¹¹ = 18981899 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 18983947.

It is not an unprimeable number, because it can be changed into a prime (18983927) 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, 412672 + ... + 412717.

It is an arithmetic number, because the mean of its divisors is an integer number (4952340).

Almost surely, 2^18983947 is an apocalyptic number.

18983947 is a deficient number, since it is larger than the sum of its proper divisors (825413).

18983947 is an equidigital number, since it uses as much as digits as its factorization.

18983947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 825412.

The product of its digits is 435456, while the sum is 49.

The square root of 18983947 is about 4357.0571490399. The cubic root of 18983947 is about 266.7649930805.

The spelling of 18983947 in words is "eighteen million, nine hundred eighty-three thousand, nine hundred forty-seven".