20181818380 has 12 divisors (see below), whose sum is σ = 42381818640. Its totient is φ = 8072727344.

The previous prime is 20181818357. The next prime is 20181818381. The reversal of 20181818380 is 8381818102.

It is not an unprimeable number, because it can be changed into a prime (20181818381) 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, 504545440 + ... + 504545479.

It is an arithmetic number, because the mean of its divisors is an integer number (3531818220).

Almost surely, 2^20181818380 is an apocalyptic number.

20181818380 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20181818380 is an abundant number, since it is smaller than the sum of its proper divisors (22200000260).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20181818380 is a wasteful number, since it uses less digits than its factorization.

20181818380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1009090928 (or 1009090926 counting only the distinct ones).

The product of its (nonzero) digits is 24576, while the sum is 40.

The spelling of 20181818380 in words is "twenty billion, one hundred eighty-one million, eight hundred eighteen thousand, three hundred eighty".