1166611644 has 144 divisors (see below), whose sum is σ = 3302208000. Its totient is φ = 344298240.

The previous prime is 1166611643. The next prime is 1166611651. The reversal of 1166611644 is 4461166611.

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

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 1166611599 and 1166611608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1166611643) by changing a digit.

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, 2784067 + ... + 2784485.

It is an arithmetic number, because the mean of its divisors is an integer number (22932000).

Almost surely, 2^1166611644 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1166611644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1651104000).

1166611644 is an abundant number, since it is smaller than the sum of its proper divisors (2135596356).

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

1166611644 is a wasteful number, since it uses less digits than its factorization.

1166611644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 608 (or 603 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 1166611644 is about 34155.6970943355. The cubic root of 1166611644 is about 1052.7100496850.

The spelling of 1166611644 in words is "one billion, one hundred sixty-six million, six hundred eleven thousand, six hundred forty-four".