18621340208 has 20 divisors (see below), whose sum is σ = 36089360520. Its totient is φ = 9307956864.

The previous prime is 18621340181. The next prime is 18621340237. The reversal of 18621340208 is 80204312681.

It is a super-2 number, since 2×18621340208² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112373 + ... + 223316.

It is an arithmetic number, because the mean of its divisors is an integer number (1804468026).

Almost surely, 2^18621340208 is an apocalyptic number.

It is an amenable number.

18621340208 is a deficient number, since it is larger than the sum of its proper divisors (17468020312).

18621340208 is a wasteful number, since it uses less digits than its factorization.

18621340208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 339164 (or 339158 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 35.

Adding to 18621340208 its reverse (80204312681), we get a palindrome (98825652889).

The spelling of 18621340208 in words is "eighteen billion, six hundred twenty-one million, three hundred forty thousand, two hundred eight".