1661166012 has 96 divisors (see below), whose sum is σ = 4292870400. Its totient is φ = 495774720.

The previous prime is 1661165977. The next prime is 1661166019. The reversal of 1661166012 is 2106611661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661166019) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4759614 + ... + 4759962.

It is an arithmetic number, because the mean of its divisors is an integer number (44717400).

Almost surely, 2^1661166012 is an apocalyptic number.

1661166012 is a gapful number since it is divisible by the number (12) 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 1661166012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2146435200).

1661166012 is an abundant number, since it is smaller than the sum of its proper divisors (2631704388).

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

1661166012 is a wasteful number, since it uses less digits than its factorization.

1661166012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 811 (or 809 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 1661166012 is about 40757.4043825168. The cubic root of 1661166012 is about 1184.3253144544.

Adding to 1661166012 its reverse (2106611661), we get a palindrome (3767777673).

The spelling of 1661166012 in words is "one billion, six hundred sixty-one million, one hundred sixty-six thousand, twelve".