1665431040 has 320 divisors, whose sum is σ = 6555580416. Its totient is φ = 351240192.

The previous prime is 1665431023. The next prime is 1665431051. The reversal of 1665431040 is 401345661.

It is a tau number, because it is divible by the number of its divisors (320).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 1665430989 and 1665431007.

It is a congruent 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 31 ways as a sum of consecutive naturals, for example, 697689 + ... + 700071.

Almost surely, 2^1665431040 is an apocalyptic number.

1665431040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1665431040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3277790208).

1665431040 is an abundant number, since it is smaller than the sum of its proper divisors (4890149376).

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

1665431040 is a wasteful number, since it uses less digits than its factorization.

1665431040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2429 (or 2413 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 1665431040 is about 40809.6929662550. The cubic root of 1665431040 is about 1185.3380295781.

The spelling of 1665431040 in words is "one billion, six hundred sixty-five million, four hundred thirty-one thousand, forty".