266321860 has 72 divisors (see below), whose sum is σ = 684875520. Its totient is φ = 86498496.

The previous prime is 266321827. The next prime is 266321863. The reversal of 266321860 is 68123662.

It is a happy number.

266321860 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×266321860² = 141854666227719200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (266321863) 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, 11469 + ... + 25771.

It is an arithmetic number, because the mean of its divisors is an integer number (9512160).

Almost surely, 2^266321860 is an apocalyptic number.

266321860 is a gapful number since it is divisible by the number (20) 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 266321860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (342437760).

266321860 is an abundant number, since it is smaller than the sum of its proper divisors (418553660).

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

266321860 is a wasteful number, since it uses less digits than its factorization.

266321860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14345 (or 14336 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 266321860 is about 16319.3706986513. The cubic root of 266321860 is about 643.3820474326.

The spelling of 266321860 in words is "two hundred sixty-six million, three hundred twenty-one thousand, eight hundred sixty".