18819729 has 16 divisors (see below), whose sum is σ = 28002240. Its totient is φ = 12492000.

The previous prime is 18819721. The next prime is 18819733. The reversal of 18819729 is 92791881.

It is not a de Polignac number, because 18819729 - 2³ = 18819721 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18819721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5389 + ... + 8165.

It is an arithmetic number, because the mean of its divisors is an integer number (1750140).

Almost surely, 2^18819729 is an apocalyptic number.

It is an amenable number.

18819729 is a deficient number, since it is larger than the sum of its proper divisors (9182511).

18819729 is a wasteful number, since it uses less digits than its factorization.

18819729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3037 (or 3031 counting only the distinct ones).

The product of its digits is 72576, while the sum is 45.

The square root of 18819729 is about 4338.1711584491. The cubic root of 18819729 is about 265.9935598720.

The spelling of 18819729 in words is "eighteen million, eight hundred nineteen thousand, seven hundred twenty-nine".