1165561560000 has 840 divisors, whose sum is σ = 4373089763328. Its totient is φ = 296352000000.

The previous prime is 1165561559923. The next prime is 1165561560001. The reversal of 1165561560000 is 651655611.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1165561560001) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 792359265 + ... + 792360735.

Almost surely, 2^{1165561560000} is an apocalyptic number.

1165561560000 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 1165561560000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2186544881664).

1165561560000 is an abundant number, since it is smaller than the sum of its proper divisors (3207528203328).

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

1165561560000 is a wasteful number, since it uses less digits than its factorization.

1165561560000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1611 (or 1583 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 36.

The spelling of 1165561560000 in words is "one trillion, one hundred sixty-five billion, five hundred sixty-one million, five hundred sixty thousand".