1665587340 has 96 divisors (see below), whose sum is σ = 5210761920. Its totient is φ = 441676800.

The previous prime is 1665587309. The next prime is 1665587351. The reversal of 1665587340 is 437855661.

1665587340 is a `hidden beast` number, since 1 + 6 + 65 + 587 + 3 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 89220 + ... + 106260.

It is an arithmetic number, because the mean of its divisors is an integer number (54278770).

Almost surely, 2^1665587340 is an apocalyptic number.

1665587340 is a gapful number since it is divisible by the number (10) 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 1665587340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2605380960).

1665587340 is an abundant number, since it is smaller than the sum of its proper divisors (3545174580).

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

1665587340 is a wasteful number, since it uses less digits than its factorization.

1665587340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17240 (or 17232 counting only the distinct ones).

The product of its (nonzero) digits is 604800, while the sum is 45.

The square root of 1665587340 is about 40811.6079075549. The cubic root of 1665587340 is about 1185.3751095760.

The spelling of 1665587340 in words is "one billion, six hundred sixty-five million, five hundred eighty-seven thousand, three hundred forty".