18491743 has 4 divisors (see below), whose sum is σ = 18602640. Its totient is φ = 18380848.

The previous prime is 18491719. The next prime is 18491771. The reversal of 18491743 is 34719481.

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 18491743 - 2²¹ = 16394591 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18491713) 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, 55198 + ... + 55531.

It is an arithmetic number, because the mean of its divisors is an integer number (4650660).

Almost surely, 2^18491743 is an apocalyptic number.

18491743 is a deficient number, since it is larger than the sum of its proper divisors (110897).

18491743 is a wasteful number, since it uses less digits than its factorization.

18491743 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110896.

The product of its digits is 24192, while the sum is 37.

The square root of 18491743 is about 4300.2026696424. The cubic root of 18491743 is about 264.4392700316.

The spelling of 18491743 in words is "eighteen million, four hundred ninety-one thousand, seven hundred forty-three".