1181820640 has 384 divisors, whose sum is σ = 3852914688. Its totient is φ = 330670080.

The previous prime is 1181820623. The next prime is 1181820641. The reversal of 1181820640 is 460281811.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1181820641) 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 63 ways as a sum of consecutive naturals, for example, 7527442 + ... + 7527598.

It is an arithmetic number, because the mean of its divisors is an integer number (10033632).

Almost surely, 2^1181820640 is an apocalyptic number.

1181820640 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 1181820640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1926457344).

1181820640 is an abundant number, since it is smaller than the sum of its proper divisors (2671094048).

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

1181820640 is a wasteful number, since it uses less digits than its factorization.

1181820640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250 (or 242 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 31.

The square root of 1181820640 is about 34377.6183002837. The cubic root of 1181820640 is about 1057.2650033825.

The spelling of 1181820640 in words is "one billion, one hundred eighty-one million, eight hundred twenty thousand, six hundred forty".