18747242 has 4 divisors (see below), whose sum is σ = 28120866. Its totient is φ = 9373620.

The previous prime is 18747241. The next prime is 18747251. The reversal of 18747242 is 24274781.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24274781 = 2011 ⋅12071.

It can be written as a sum of positive squares in only one way, i.e., 12033961 + 6713281 = 3469^2 + 2591^2 .

It is not an unprimeable number, because it can be changed into a prime (18747241) 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 as a sum of consecutive naturals, namely, 4686809 + ... + 4686812.

Almost surely, 2^18747242 is an apocalyptic number.

18747242 is a deficient number, since it is larger than the sum of its proper divisors (9373624).

18747242 is an equidigital number, since it uses as much as digits as its factorization.

18747242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9373623.

The product of its digits is 25088, while the sum is 35.

The square root of 18747242 is about 4329.8085408018. The cubic root of 18747242 is about 265.6516158243.

The spelling of 18747242 in words is "eighteen million, seven hundred forty-seven thousand, two hundred forty-two".