266987520 has 144 divisors (see below), whose sum is σ = 925650180. Its totient is φ = 71172096.

The previous prime is 266987509. The next prime is 266987551. The reversal of 266987520 is 25789662.

It can be written as a sum of positive squares in 2 ways, for example, as 244859904 + 22127616 = 15648^2 + 4704^2 .

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 90712 + ... + 93608.

Almost surely, 2^266987520 is an apocalyptic number.

266987520 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 266987520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (462825090).

266987520 is an abundant number, since it is smaller than the sum of its proper divisors (658662660).

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

266987520 is a wasteful number, since it uses less digits than its factorization.

266987520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2930 (or 2907 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The square root of 266987520 is about 16339.7527521074. The cubic root of 266987520 is about 643.9176366768.

The spelling of 266987520 in words is "two hundred sixty-six million, nine hundred eighty-seven thousand, five hundred twenty".