266478138 has 48 divisors (see below), whose sum is σ = 616524480. Its totient is φ = 82982592.

The previous prime is 266478127. The next prime is 266478209. The reversal of 266478138 is 831874662.

266478138 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 266478093 and 266478102.

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, 10318 + ... + 25286.

It is an arithmetic number, because the mean of its divisors is an integer number (12844260).

Almost surely, 2^266478138 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 266478138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (308262240).

266478138 is an abundant number, since it is smaller than the sum of its proper divisors (350046342).

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

266478138 is a wasteful number, since it uses less digits than its factorization.

266478138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15043 (or 15040 counting only the distinct ones).

The product of its digits is 387072, while the sum is 45.

The square root of 266478138 is about 16324.1581099915. The cubic root of 266478138 is about 643.5078686214.

The spelling of 266478138 in words is "two hundred sixty-six million, four hundred seventy-eight thousand, one hundred thirty-eight".