1665415404 has 120 divisors (see below), whose sum is σ = 4634905968. Its totient is φ = 519644160.

The previous prime is 1665415403. The next prime is 1665415439. The reversal of 1665415404 is 4045145661.

1665415404 is a `hidden beast` number, since 1 + 66 + 54 + 1 + 540 + 4 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (1665415403) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1161472 + ... + 1162904.

Almost surely, 2^1665415404 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 1665415404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2317452984).

1665415404 is an abundant number, since it is smaller than the sum of its proper divisors (2969490564).

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

1665415404 is a wasteful number, since it uses less digits than its factorization.

1665415404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1677 (or 1666 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The square root of 1665415404 is about 40809.5013936706. The cubic root of 1665415404 is about 1185.3343200272.

The spelling of 1665415404 in words is "one billion, six hundred sixty-five million, four hundred fifteen thousand, four hundred four".