1665432405 has 48 divisors (see below), whose sum is σ = 3552931200. Its totient is φ = 702774144.

The previous prime is 1665432361. The next prime is 1665432413. The reversal of 1665432405 is 5042345661.

It is not a de Polignac number, because 1665432405 - 2²⁷ = 1531214677 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1665432405.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 199255 + ... + 207444.

It is an arithmetic number, because the mean of its divisors is an integer number (74019400).

Almost surely, 2^1665432405 is an apocalyptic number.

1665432405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1665432405 is an abundant number, since it is smaller than the sum of its proper divisors (1887498795).

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

1665432405 is a wasteful number, since it uses less digits than its factorization.

1665432405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 406730 (or 406727 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 1665432405 is about 40809.7096902196. The cubic root of 1665432405 is about 1185.3383534154.

The spelling of 1665432405 in words is "one billion, six hundred sixty-five million, four hundred thirty-two thousand, four hundred five".