1166555642520 has 64 divisors (see below), whose sum is σ = 3505629093120. Its totient is φ = 310551534464.

The previous prime is 1166555642519. The next prime is 1166555642521. The reversal of 1166555642520 is 252465556611.

It is an interprime number because it is at equal distance from previous prime (1166555642519) and next prime (1166555642521).

It is a self number, because there is not a number n which added to its sum of digits gives 1166555642520.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1166555642521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8210052 + ... + 8350931.

It is an arithmetic number, because the mean of its divisors is an integer number (54775454580).

Almost surely, 2^{1166555642520} is an apocalyptic number.

1166555642520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1166555642520 is an abundant number, since it is smaller than the sum of its proper divisors (2339073450600).

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

1166555642520 is a wasteful number, since it uses less digits than its factorization.

1166555642520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16561584 (or 16561580 counting only the distinct ones).

The product of its (nonzero) digits is 2160000, while the sum is 48.

The spelling of 1166555642520 in words is "one trillion, one hundred sixty-six billion, five hundred fifty-five million, six hundred forty-two thousand, five hundred twenty".