266778864 has 180 divisors, whose sum is σ = 837430776. Its totient is φ = 79200000.

The previous prime is 266778851. The next prime is 266778881. The reversal of 266778864 is 468877662.

It is a self number, because there is not a number n which added to its sum of digits gives 266778864.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1062739 + ... + 1062989.

Almost surely, 2^266778864 is an apocalyptic number.

266778864 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 266778864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (418715388).

266778864 is an abundant number, since it is smaller than the sum of its proper divisors (570651912).

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

266778864 is a wasteful number, since it uses less digits than its factorization.

266778864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 348 (or 328 counting only the distinct ones).

The product of its digits is 5419008, while the sum is 54.

The square root of 266778864 is about 16333.3665850002. The cubic root of 266778864 is about 643.7498481918.

The spelling of 266778864 in words is "two hundred sixty-six million, seven hundred seventy-eight thousand, eight hundred sixty-four".