664007940 has 36 divisors (see below), whose sum is σ = 2014157964. Its totient is φ = 177068736.

The previous prime is 664007893. The next prime is 664007951. The reversal of 664007940 is 49700466.

664007940 is a `hidden beast` number, since 6 + 640 + 0 + 7 + 9 + 4 + 0 = 666.

664007940 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 420086016 + 243921924 = 20496^2 + 15618^2 .

It is a tau number, because it is divible by the number of its divisors (36).

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

It is a junction number, because it is equal to n+sod(n) for n = 664007895 and 664007904.

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, 1844287 + ... + 1844646.

Almost surely, 2^664007940 is an apocalyptic number.

664007940 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

664007940 is an abundant number, since it is smaller than the sum of its proper divisors (1350150024).

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

664007940 is a wasteful number, since it uses less digits than its factorization.

664007940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3688948 (or 3688943 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 664007940 is about 25768.3515188690. The cubic root of 664007940 is about 872.4176116708.

The spelling of 664007940 in words is "six hundred sixty-four million, seven thousand, nine hundred forty".