18618989371 has 16 divisors (see below), whose sum is σ = 20470233600. Its totient is φ = 16856313408.

The previous prime is 18618989351. The next prime is 18618989381. The reversal of 18618989371 is 17398981681.

It is a cyclic number.

It is not a de Polignac number, because 18618989371 - 2¹¹ = 18618987323 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18618989351) 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, 459970 + ... + 498808.

It is an arithmetic number, because the mean of its divisors is an integer number (1279389600).

Almost surely, 2^18618989371 is an apocalyptic number.

18618989371 is a deficient number, since it is larger than the sum of its proper divisors (1851244229).

18618989371 is a wasteful number, since it uses less digits than its factorization.

18618989371 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39978.

The product of its digits is 5225472, while the sum is 61.

The spelling of 18618989371 in words is "eighteen billion, six hundred eighteen million, nine hundred eighty-nine thousand, three hundred seventy-one".