18729147 has 4 divisors (see below), whose sum is σ = 24972200. Its totient is φ = 12486096.

The previous prime is 18729119. The next prime is 18729163. The reversal of 18729147 is 74192781.

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

It is not a de Polignac number, because 18729147 - 2¹¹ = 18727099 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18729167) 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, 3121522 + ... + 3121527.

It is an arithmetic number, because the mean of its divisors is an integer number (6243050).

Almost surely, 2^18729147 is an apocalyptic number.

18729147 is a deficient number, since it is larger than the sum of its proper divisors (6243053).

18729147 is an equidigital number, since it uses as much as digits as its factorization.

18729147 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6243052.

The product of its digits is 28224, while the sum is 39.

The square root of 18729147 is about 4327.7184520253. The cubic root of 18729147 is about 265.5661185657.

The spelling of 18729147 in words is "eighteen million, seven hundred twenty-nine thousand, one hundred forty-seven".