1818755640 has 256 divisors, whose sum is σ = 6566313600. Its totient is φ = 445132800.

The previous prime is 1818755633. The next prime is 1818755651. The reversal of 1818755640 is 465578181.

1818755640 is a `hidden beast` number, since 1 + 8 + 1 + 87 + 5 + 564 + 0 = 666.

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 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, 3945010 + ... + 3945470.

Almost surely, 2^1818755640 is an apocalyptic number.

1818755640 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 1818755640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3283156800).

1818755640 is an abundant number, since it is smaller than the sum of its proper divisors (4747557960).

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

1818755640 is a wasteful number, since it uses less digits than its factorization.

1818755640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 775 (or 765 counting only the distinct ones).

The product of its (nonzero) digits is 268800, while the sum is 45.

The square root of 1818755640 is about 42646.8713975598. The cubic root of 1818755640 is about 1220.6508307398.

The spelling of 1818755640 in words is "one billion, eight hundred eighteen million, seven hundred fifty-five thousand, six hundred forty".