1664389344 has 96 divisors (see below), whose sum is σ = 4587649920. Its totient is φ = 527611392.

The previous prime is 1664389339. The next prime is 1664389357. The reversal of 1664389344 is 4439834661.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a junction number, because it is equal to n+sod(n) for n = 1664389293 and 1664389302.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 182067 + ... + 190989.

It is an arithmetic number, because the mean of its divisors is an integer number (47788020).

Almost surely, 2^1664389344 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 1664389344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2293824960).

1664389344 is an abundant number, since it is smaller than the sum of its proper divisors (2923260576).

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

1664389344 is a wasteful number, since it uses less digits than its factorization.

1664389344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9032 (or 9024 counting only the distinct ones).

The product of its digits is 1492992, while the sum is 48.

The square root of 1664389344 is about 40796.9281196514. The cubic root of 1664389344 is about 1185.0908424367.

The spelling of 1664389344 in words is "one billion, six hundred sixty-four million, three hundred eighty-nine thousand, three hundred forty-four".