1665452440 has 16 divisors (see below), whose sum is σ = 3747268080. Its totient is φ = 666180960.

The previous prime is 1665452407. The next prime is 1665452449. The reversal of 1665452440 is 442545661.

It is a self number, because there is not a number n which added to its sum of digits gives 1665452440.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1665452449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20818116 + ... + 20818195.

It is an arithmetic number, because the mean of its divisors is an integer number (234204255).

Almost surely, 2^1665452440 is an apocalyptic number.

1665452440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1665452440 is an abundant number, since it is smaller than the sum of its proper divisors (2081815640).

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

1665452440 is a wasteful number, since it uses less digits than its factorization.

1665452440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41636322 (or 41636318 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 37.

The square root of 1665452440 is about 40809.9551580249. The cubic root of 1665452440 is about 1185.3431065671.

The spelling of 1665452440 in words is "one billion, six hundred sixty-five million, four hundred fifty-two thousand, four hundred forty".