666672025440 has 96 divisors (see below), whose sum is σ = 2101767254496. Its totient is φ = 177631027200.

The previous prime is 666672025361. The next prime is 666672025493. The reversal of 666672025440 is 44520276666.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 666672025440.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1747 + ... + 1154706.

It is an arithmetic number, because the mean of its divisors is an integer number (21893408901).

Almost surely, 2^666672025440 is an apocalyptic number.

666672025440 is a gapful number since it is divisible by the number (60) 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 666672025440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1050883627248).

666672025440 is an abundant number, since it is smaller than the sum of its proper divisors (1435095229056).

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

666672025440 is a wasteful number, since it uses less digits than its factorization.

666672025440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1157672 (or 1157664 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 48.

The spelling of 666672025440 in words is "six hundred sixty-six billion, six hundred seventy-two million, twenty-five thousand, four hundred forty".