1665319992 has 64 divisors (see below), whose sum is σ = 4786629120. Its totient is φ = 472948608.

The previous prime is 1665319987. The next prime is 1665320071. The reversal of 1665319992 is 2999135661.

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, 1623 + ... + 57734.

It is an arithmetic number, because the mean of its divisors is an integer number (74791080).

Almost surely, 2^1665319992 is an apocalyptic number.

1665319992 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 1665319992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2393314560).

1665319992 is an abundant number, since it is smaller than the sum of its proper divisors (3121309128).

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

1665319992 is a wasteful number, since it uses less digits than its factorization.

1665319992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59540 (or 59536 counting only the distinct ones).

The product of its digits is 787320, while the sum is 51.

The square root of 1665319992 is about 40808.3323844531. The cubic root of 1665319992 is about 1185.3116835772.

The spelling of 1665319992 in words is "one billion, six hundred sixty-five million, three hundred nineteen thousand, nine hundred ninety-two".