666006624 has 144 divisors (see below), whose sum is σ = 2012970960. Its totient is φ = 216483840.

The previous prime is 666006589. The next prime is 666006631. The reversal of 666006624 is 426600666.

It is a tau number, because it is divible by the number of its divisors (144).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 317772 + ... + 319860.

It is an arithmetic number, because the mean of its divisors is an integer number (13978965).

Almost surely, 2^666006624 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 666006624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1006485480).

666006624 is an abundant number, since it is smaller than the sum of its proper divisors (1346964336).

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

666006624 is a wasteful number, since it uses less digits than its factorization.

666006624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2155 (or 2135 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 36.

The square root of 666006624 is about 25807.1041382019. The cubic root of 666006624 is about 873.2920693490.

It can be divided in two parts, 66600662 and 4, that added together give a palindrome (66600666).

The spelling of 666006624 in words is "six hundred sixty-six million, six thousand, six hundred twenty-four".