1918045440 has 576 divisors, whose sum is σ = 7535001600. Its totient is φ = 459841536.

The previous prime is 1918045439. The next prime is 1918045447. The reversal of 1918045440 is 445408191.

1918045440 is a `hidden beast` number, since 1 + 91 + 80 + 454 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1918045395 and 1918045404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1918045447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 15102657 + ... + 15102783.

It is an arithmetic number, because the mean of its divisors is an integer number (13081600).

Almost surely, 2^1918045440 is an apocalyptic number.

1918045440 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 1918045440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3767500800).

1918045440 is an abundant number, since it is smaller than the sum of its proper divisors (5616956160).

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

1918045440 is a wasteful number, since it uses less digits than its factorization.

1918045440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199 (or 179 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 1918045440 is about 43795.4956588003. The cubic root of 1918045440 is about 1242.4711041595.

It can be divided in two parts, 19180 and 45440, that added together give a triangular number (64620 = T₃₅₉).

The spelling of 1918045440 in words is "one billion, nine hundred eighteen million, forty-five thousand, four hundred forty".