1165639680 has 480 divisors, whose sum is σ = 4529710080. Its totient is φ = 283115520.

The previous prime is 1165639679. The next prime is 1165639693. The reversal of 1165639680 is 869365611.

1165639680 is a `hidden beast` number, since 1 + 1 + 6 + 5 + 639 + 6 + 8 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (480).

It is a super-3 number, since 3×1165639680³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 37601265 + ... + 37601295.

It is an arithmetic number, because the mean of its divisors is an integer number (9436896).

Almost surely, 2^1165639680 is an apocalyptic number.

1165639680 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 1165639680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2264855040).

1165639680 is an abundant number, since it is smaller than the sum of its proper divisors (3364070400).

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

1165639680 is an equidigital number, since it uses as much as digits as its factorization.

1165639680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90 (or 58 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The square root of 1165639680 is about 34141.4656978871. The cubic root of 1165639680 is about 1052.4176128755.

The spelling of 1165639680 in words is "one billion, one hundred sixty-five million, six hundred thirty-nine thousand, six hundred eighty".