18446729 has 4 divisors (see below), whose sum is σ = 21081984. Its totient is φ = 15811476.

The previous prime is 18446711. The next prime is 18446773. The reversal of 18446729 is 92764481.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 92764481 = 137 ⋅677113.

It is a cyclic number.

It is not a de Polignac number, because 18446729 - 2²⁰ = 17398153 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18446629) 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, 1317617 + ... + 1317630.

It is an arithmetic number, because the mean of its divisors is an integer number (5270496).

Almost surely, 2^18446729 is an apocalyptic number.

It is an amenable number.

18446729 is a deficient number, since it is larger than the sum of its proper divisors (2635255).

18446729 is an equidigital number, since it uses as much as digits as its factorization.

18446729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2635254.

The product of its digits is 96768, while the sum is 41.

The square root of 18446729 is about 4294.9655411889. The cubic root of 18446729 is about 264.2245229927.

The spelling of 18446729 in words is "eighteen million, four hundred forty-six thousand, seven hundred twenty-nine".