1660889664 has 448 divisors, whose sum is σ = 6083320320. Its totient is φ = 433520640.

The previous prime is 1660889651. The next prime is 1660889669. The reversal of 1660889664 is 4669880661.

It is a tau number, because it is divible by the number of its divisors (448).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 1660889664.

It is not an unprimeable number, because it can be changed into a prime (1660889669) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8430814 + ... + 8431010.

It is an arithmetic number, because the mean of its divisors is an integer number (13578840).

Almost surely, 2^1660889664 is an apocalyptic number.

1660889664 is a gapful number since it is divisible by the number (14) 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 1660889664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3041660160).

1660889664 is an abundant number, since it is smaller than the sum of its proper divisors (4422430656).

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

1660889664 is a wasteful number, since it uses less digits than its factorization.

1660889664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 283 (or 267 counting only the distinct ones).

The product of its (nonzero) digits is 2985984, while the sum is 54.

The square root of 1660889664 is about 40754.0140845046. The cubic root of 1660889664 is about 1184.2596368760.

The spelling of 1660889664 in words is "one billion, six hundred sixty million, eight hundred eighty-nine thousand, six hundred sixty-four".