1665673290 has 96 divisors (see below), whose sum is σ = 4491676800. Its totient is φ = 427754880.

The previous prime is 1665673267. The next prime is 1665673333. The reversal of 1665673290 is 923765661.

1665673290 is a `hidden beast` number, since 1 + 66 + 567 + 3 + 29 + 0 = 666.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

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

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1615075 + ... + 1616105.

It is an arithmetic number, because the mean of its divisors is an integer number (46788300).

Almost surely, 2^1665673290 is an apocalyptic number.

1665673290 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 1665673290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2245838400).

1665673290 is an abundant number, since it is smaller than the sum of its proper divisors (2826003510).

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

1665673290 is a wasteful number, since it uses less digits than its factorization.

1665673290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1692 (or 1689 counting only the distinct ones).

The product of its (nonzero) digits is 408240, while the sum is 45.

The square root of 1665673290 is about 40812.6609032050. The cubic root of 1665673290 is about 1185.3954990278.

The spelling of 1665673290 in words is "one billion, six hundred sixty-five million, six hundred seventy-three thousand, two hundred ninety".