1918181880 has 96 divisors (see below), whose sum is σ = 6248502000. Its totient is φ = 510332928.

The previous prime is 1918181869. The next prime is 1918181897. The reversal of 1918181880 is 881818191.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 155707 + ... + 167573.

Almost surely, 2^1918181880 is an apocalyptic number.

1918181880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1918181880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3124251000).

1918181880 is an abundant number, since it is smaller than the sum of its proper divisors (4330320120).

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

1918181880 is a wasteful number, since it uses less digits than its factorization.

1918181880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12333 (or 12326 counting only the distinct ones).

The product of its (nonzero) digits is 36864, while the sum is 45.

The square root of 1918181880 is about 43797.0533255378. The cubic root of 1918181880 is about 1242.5005644866.

The spelling of 1918181880 in words is "one billion, nine hundred eighteen million, one hundred eighty-one thousand, eight hundred eighty".