666626436 has 120 divisors (see below), whose sum is σ = 2004340800. Its totient is φ = 189252288.

The previous prime is 666626431. The next prime is 666626453. The reversal of 666626436 is 634626666.

It is a nude number because it is divisible by every one of its digits.

It is a junction number, because it is equal to n+sod(n) for n = 666626391 and 666626400.

It is not an unprimeable number, because it can be changed into a prime (666626431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 391515 + ... + 393213.

It is an arithmetic number, because the mean of its divisors is an integer number (16702840).

Almost surely, 2^666626436 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 666626436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1002170400).

666626436 is an abundant number, since it is smaller than the sum of its proper divisors (1337714364).

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

666626436 is a wasteful number, since it uses less digits than its factorization.

666626436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1895 (or 1884 counting only the distinct ones).

The product of its digits is 1119744, while the sum is 45.

The square root of 666626436 is about 25819.1098994524. The cubic root of 666626436 is about 873.5628920206.

The spelling of 666626436 in words is "six hundred sixty-six million, six hundred twenty-six thousand, four hundred thirty-six".