666259812 has 72 divisors (see below), whose sum is σ = 1767164672. Its totient is φ = 211377600.

The previous prime is 666259807. The next prime is 666259817. The reversal of 666259812 is 218952666.

666259812 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (666259807) and next prime (666259817).

It is not an unprimeable number, because it can be changed into a prime (666259817) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 63183 + ... + 72969.

Almost surely, 2^666259812 is an apocalyptic number.

666259812 is a gapful number since it is divisible by the number (62) 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 666259812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (883582336).

666259812 is an abundant number, since it is smaller than the sum of its proper divisors (1100904860).

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

666259812 is a wasteful number, since it uses less digits than its factorization.

666259812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9889 (or 9884 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The square root of 666259812 is about 25812.0090655493. The cubic root of 666259812 is about 873.4027184285.

The spelling of 666259812 in words is "six hundred sixty-six million, two hundred fifty-nine thousand, eight hundred twelve".