918181820 has 12 divisors (see below), whose sum is σ = 1928181864. Its totient is φ = 367272720.

The previous prime is 918181813. The next prime is 918181837. The reversal of 918181820 is 28181819.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22954526 + ... + 22954565.

It is an arithmetic number, because the mean of its divisors is an integer number (160681822).

Almost surely, 2^918181820 is an apocalyptic number.

It is an amenable number.

918181820 is an abundant number, since it is smaller than the sum of its proper divisors (1010000044).

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

918181820 is a wasteful number, since it uses less digits than its factorization.

918181820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45909100 (or 45909098 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 38.

The square root of 918181820 is about 30301.5151436360. The cubic root of 918181820 is about 971.9477002236.

The spelling of 918181820 in words is "nine hundred eighteen million, one hundred eighty-one thousand, eight hundred twenty".