1665365364 has 72 divisors (see below), whose sum is σ = 4619101032. Its totient is φ = 502744320.

The previous prime is 1665365363. The next prime is 1665365389. The reversal of 1665365364 is 4635635661.

1665365364 is a `hidden beast` number, since 1 + 6 + 6 + 536 + 53 + 64 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 419840100 + 1245525264 = 20490^2 + 35292^2 .

It is a super-2 number, since 2×1665365364² = 5546883591221704992, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1665365363) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8767 + ... + 58374.

It is an arithmetic number, because the mean of its divisors is an integer number (64154181).

Almost surely, 2^1665365364 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 1665365364, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2309550516).

1665365364 is an abundant number, since it is smaller than the sum of its proper divisors (2953735668).

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

1665365364 is a wasteful number, since it uses less digits than its factorization.

1665365364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67217 (or 67212 counting only the distinct ones).

The product of its digits is 1166400, while the sum is 45.

The square root of 1665365364 is about 40808.8882965464. Note that the first 3 decimals coincide. The cubic root of 1665365364 is about 1185.3224481697.

The spelling of 1665365364 in words is "one billion, six hundred sixty-five million, three hundred sixty-five thousand, three hundred sixty-four".