1820418138 has 120 divisors (see below), whose sum is σ = 5124526176. Its totient is φ = 472800240.

The previous prime is 1820418121. The next prime is 1820418143. The reversal of 1820418138 is 8318140281.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 130581 + ... + 143847.

Almost surely, 2^1820418138 is an apocalyptic number.

1820418138 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1820418138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2562263088).

1820418138 is an abundant number, since it is smaller than the sum of its proper divisors (3304108038).

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

1820418138 is a wasteful number, since it uses less digits than its factorization.

1820418138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13310 (or 13290 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 36.

The square root of 1820418138 is about 42666.3583869071. The cubic root of 1820418138 is about 1221.0226438459.

The spelling of 1820418138 in words is "one billion, eight hundred twenty million, four hundred eighteen thousand, one hundred thirty-eight".