1191640320 has 432 divisors, whose sum is σ = 4542217680. Its totient is φ = 286654464.

The previous prime is 1191640301. The next prime is 1191640337. The reversal of 1191640320 is 230461911.

1191640320 is a `hidden beast` number, since 1 + 19 + 1 + 640 + 3 + 2 + 0 = 666.

1191640320 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 8 ways, for example, as 20358144 + 1171282176 = 4512^2 + 34224^2 .

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 10932426 + ... + 10932534.

Almost surely, 2^1191640320 is an apocalyptic number.

1191640320 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 1191640320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2271108840).

1191640320 is an abundant number, since it is smaller than the sum of its proper divisors (3350577360).

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

1191640320 is a wasteful number, since it uses less digits than its factorization.

1191640320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222 (or 205 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 1191640320 is about 34520.1436845214. The cubic root of 1191640320 is about 1060.1851818394.

The spelling of 1191640320 in words is "one billion, one hundred ninety-one million, six hundred forty thousand, three hundred twenty".