266641920 has 240 divisors, whose sum is σ = 942207552. Its totient is φ = 69672960.

The previous prime is 266641909. The next prime is 266641937. The reversal of 266641920 is 29146662.

It is a tau number, because it is divible by the number of its divisors (240).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1635759 + ... + 1635921.

Almost surely, 2^266641920 is an apocalyptic number.

266641920 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 266641920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (471103776).

266641920 is an abundant number, since it is smaller than the sum of its proper divisors (675565632).

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

266641920 is a wasteful number, since it uses less digits than its factorization.

266641920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263 (or 244 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 266641920 is about 16329.1738921478. The cubic root of 266641920 is about 643.6396785845.

The spelling of 266641920 in words is "two hundred sixty-six million, six hundred forty-one thousand, nine hundred twenty".