1818573640 has 64 divisors (see below), whose sum is σ = 4665774960. Its totient is φ = 631971840.

The previous prime is 1818573613. The next prime is 1818573641. The reversal of 1818573640 is 463758181.

It can be written as a sum of positive squares in 8 ways, for example, as 900120004 + 918453636 = 30002^2 + 30306^2 .

It is a super-3 number, since 3×1818573640³ (a number of 29 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (1818573641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 94021 + ... + 111700.

Almost surely, 2^1818573640 is an apocalyptic number.

1818573640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1818573640 is an abundant number, since it is smaller than the sum of its proper divisors (2847201320).

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

1818573640 is a wasteful number, since it uses less digits than its factorization.

1818573640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205762 (or 205758 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 43.

The square root of 1818573640 is about 42644.7375416944. The cubic root of 1818573640 is about 1220.6101131823.

The spelling of 1818573640 in words is "one billion, eight hundred eighteen million, five hundred seventy-three thousand, six hundred forty".