1660601664 has 126 divisors (see below), whose sum is σ = 4834831326. Its totient is φ = 544942080.

The previous prime is 1660601659. The next prime is 1660601687. The reversal of 1660601664 is 4661060661.

It can be written as a sum of positive squares in 3 ways, for example, as 262440000 + 1398161664 = 16200^2 + 37392^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 3069234 + ... + 3069774.

Almost surely, 2^1660601664 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 1660601664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2417415663).

1660601664 is an abundant number, since it is smaller than the sum of its proper divisors (3174229662).

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

1660601664 is an equidigital number, since it uses as much as digits as its factorization.

1660601664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 705 (or 619 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 1660601664 is about 40750.4805370440. The cubic root of 1660601664 is about 1184.1911823005.

The spelling of 1660601664 in words is "one billion, six hundred sixty million, six hundred one thousand, six hundred sixty-four".