18705943 has 4 divisors (see below), whose sum is σ = 18727920. Its totient is φ = 18683968.

The previous prime is 18705941. The next prime is 18705949. The reversal of 18705943 is 34950781.

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 18705943 - 2¹ = 18705941 is a prime.

It is a super-4 number, since 4×18705943⁴ (a number of 30 digits) contains 4444 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 (18705941) 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, 9658 + ... + 11431.

It is an arithmetic number, because the mean of its divisors is an integer number (4681980).

Almost surely, 2^18705943 is an apocalyptic number.

18705943 is a deficient number, since it is larger than the sum of its proper divisors (21977).

18705943 is an equidigital number, since it uses as much as digits as its factorization.

18705943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21976.

The product of its (nonzero) digits is 30240, while the sum is 37.

The square root of 18705943 is about 4325.0367628495. The cubic root of 18705943 is about 265.4564011148.

The spelling of 18705943 in words is "eighteen million, seven hundred five thousand, nine hundred forty-three".