18198649 has 12 divisors (see below), whose sum is σ = 21472128. Its totient is φ = 15376200.

The previous prime is 18198641. The next prime is 18198659. The reversal of 18198649 is 94689181.

It is not a de Polignac number, because 18198649 - 2³ = 18198641 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18198599 and 18198608.

It is not an unprimeable number, because it can be changed into a prime (18198641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 864 + ... + 6094.

It is an arithmetic number, because the mean of its divisors is an integer number (1789344).

Almost surely, 2^18198649 is an apocalyptic number.

It is an amenable number.

18198649 is a deficient number, since it is larger than the sum of its proper divisors (3273479).

18198649 is an equidigital number, since it uses as much as digits as its factorization.

18198649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5316 (or 5309 counting only the distinct ones).

The product of its digits is 124416, while the sum is 46.

The square root of 18198649 is about 4265.9874589595. The cubic root of 18198649 is about 263.0347026837.

The spelling of 18198649 in words is "eighteen million, one hundred ninety-eight thousand, six hundred forty-nine".