266321664 has 216 divisors, whose sum is σ = 898133600. Its totient is φ = 75866112.

The previous prime is 266321659. The next prime is 266321683. The reversal of 266321664 is 466123662.

266321664 is a `hidden beast` number, since 2 + 6 + 632 + 16 + 6 + 4 = 666.

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

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

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, 790104 + ... + 790440.

Almost surely, 2^266321664 is an apocalyptic number.

266321664 is a gapful number since it is divisible by the number (24) 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 266321664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (449066800).

266321664 is an abundant number, since it is smaller than the sum of its proper divisors (631811936).

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

266321664 is an equidigital number, since it uses as much as digits as its factorization.

266321664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 380 (or 349 counting only the distinct ones).

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

The square root of 266321664 is about 16319.3646935167. The cubic root of 266321664 is about 643.3818895999.

The spelling of 266321664 in words is "two hundred sixty-six million, three hundred twenty-one thousand, six hundred sixty-four".