1665502164 has 72 divisors (see below), whose sum is σ = 4429407528. Its totient is φ = 526970880.

The previous prime is 1665502159. The next prime is 1665502169. The reversal of 1665502164 is 4612055661.

It is an interprime number because it is at equal distance from previous prime (1665502159) and next prime (1665502169).

It can be written as a sum of positive squares in 4 ways, for example, as 349989264 + 1315512900 = 18708^2 + 36270^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1665502169) 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, 39364 + ... + 69860.

It is an arithmetic number, because the mean of its divisors is an integer number (61519549).

Almost surely, 2^1665502164 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 1665502164, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2214703764).

1665502164 is an abundant number, since it is smaller than the sum of its proper divisors (2763905364).

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

1665502164 is a wasteful number, since it uses less digits than its factorization.

1665502164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30585 (or 30580 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The square root of 1665502164 is about 40810.5643675752. The cubic root of 1665502164 is about 1185.3549030441.

The spelling of 1665502164 in words is "one billion, six hundred sixty-five million, five hundred two thousand, one hundred sixty-four".