1918398880 has 24 divisors (see below), whose sum is σ = 4532217732. Its totient is φ = 767359488.

The previous prime is 1918398871. The next prime is 1918398887. The reversal of 1918398880 is 888938191.

It can be written as a sum of positive squares in 2 ways, for example, as 1913887504 + 4511376 = 43748^2 + 2124^2 .

It is not an unprimeable number, because it can be changed into a prime (1918398887) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5994837 + ... + 5995156.

Almost surely, 2^1918398880 is an apocalyptic number.

1918398880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1918398880 is an abundant number, since it is smaller than the sum of its proper divisors (2613818852).

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

1918398880 is a wasteful number, since it uses less digits than its factorization.

1918398880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11990008 (or 11990000 counting only the distinct ones).

The product of its (nonzero) digits is 995328, while the sum is 55.

The square root of 1918398880 is about 43799.5305910920. The cubic root of 1918398880 is about 1242.5474165706.

The spelling of 1918398880 in words is "one billion, nine hundred eighteen million, three hundred ninety-eight thousand, eight hundred eighty".