18198913 has 4 divisors (see below), whose sum is σ = 18337968. Its totient is φ = 18059860.

The previous prime is 18198899. The next prime is 18198937. The reversal of 18198913 is 31989181.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 18198913 - 2¹³ = 18190721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18198613) 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, 69331 + ... + 69592.

It is an arithmetic number, because the mean of its divisors is an integer number (4584492).

Almost surely, 2^18198913 is an apocalyptic number.

It is an amenable number.

18198913 is a deficient number, since it is larger than the sum of its proper divisors (139055).

18198913 is a wasteful number, since it uses less digits than its factorization.

18198913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139054.

The product of its digits is 15552, while the sum is 40.

The square root of 18198913 is about 4266.0184012730. The cubic root of 18198913 is about 263.0359745881.

The spelling of 18198913 in words is "eighteen million, one hundred ninety-eight thousand, nine hundred thirteen".