1661091183360 has 2880 divisors, whose sum is σ = 7672251654144. Its totient is φ = 334430208000.

The previous prime is 1661091183347. The next prime is 1661091183361. The reversal of 1661091183360 is 633811901661.

1661091183360 is a `hidden beast` number, since 1 + 6 + 6 + 109 + 1 + 183 + 360 = 666.

It is a tau number, because it is divible by the number of its divisors (2880).

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

It is not an unprimeable number, because it can be changed into a prime (1661091183361) 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 319 ways as a sum of consecutive naturals, for example, 16446447310 + ... + 16446447410.

Almost surely, 2^{1661091183360} is an apocalyptic number.

1661091183360 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 1661091183360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3836125827072).

1661091183360 is an abundant number, since it is smaller than the sum of its proper divisors (6011160470784).

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

1661091183360 is a wasteful number, since it uses less digits than its factorization.

1661091183360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232 (or 209 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The spelling of 1661091183360 in words is "one trillion, six hundred sixty-one billion, ninety-one million, one hundred eighty-three thousand, three hundred sixty".