1665544290 has 64 divisors (see below), whose sum is σ = 4093428096. Its totient is φ = 433585152.

The previous prime is 1665544267. The next prime is 1665544297. The reversal of 1665544290 is 924455661.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1665544297) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 223464 + ... + 230796.

It is an arithmetic number, because the mean of its divisors is an integer number (63959814).

Almost surely, 2^1665544290 is an apocalyptic number.

1665544290 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1665544290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2046714048).

1665544290 is an abundant number, since it is smaller than the sum of its proper divisors (2427883806).

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

1665544290 is a wasteful number, since it uses less digits than its factorization.

1665544290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7523.

The product of its (nonzero) digits is 259200, while the sum is 42.

The square root of 1665544290 is about 40811.0804806734. The cubic root of 1665544290 is about 1185.3648967946.

The spelling of 1665544290 in words is "one billion, six hundred sixty-five million, five hundred forty-four thousand, two hundred ninety".