1665670320 has 60 divisors (see below), whose sum is σ = 5593878576. Its totient is φ = 444178560.

The previous prime is 1665670309. The next prime is 1665670337. The reversal of 1665670320 is 230765661.

1665670320 is a `hidden beast` number, since 1 + 66 + 567 + 0 + 32 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (60).

It is a super-2 number, since 2×1665670320² = 5548915229857804800, which contains 22 as substring.

It is a Smith number, since the sum of its digits (36) 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 (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1155996 + ... + 1157435.

Almost surely, 2^1665670320 is an apocalyptic number.

1665670320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1665670320 is an abundant number, since it is smaller than the sum of its proper divisors (3928208256).

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

1665670320 is a wasteful number, since it uses less digits than its factorization.

1665670320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2313450 (or 2313441 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 36.

The square root of 1665670320 is about 40812.6245174211. The cubic root of 1665670320 is about 1185.3947944825.

The spelling of 1665670320 in words is "one billion, six hundred sixty-five million, six hundred seventy thousand, three hundred twenty".