266401565100 has 864 divisors, whose sum is σ = 1000285977600. Its totient is φ = 58563993600.

The previous prime is 266401565069. The next prime is 266401565107. The reversal of 266401565100 is 1565104662.

266401565100 is a `hidden beast` number, since 2 + 6 + 640 + 1 + 5 + 6 + 5 + 1 + 0 + 0 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (266401565107) by changing a digit.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 1114650781 + ... + 1114651019.

It is an arithmetic number, because the mean of its divisors is an integer number (1157738400).

Almost surely, 2^266401565100 is an apocalyptic number.

266401565100 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 266401565100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (500142988800).

266401565100 is an abundant number, since it is smaller than the sum of its proper divisors (733884412500).

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

266401565100 is a wasteful number, since it uses less digits than its factorization.

266401565100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 503 (or 493 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

Adding to 266401565100 its reverse (1565104662), we get a palindrome (267966669762).

The spelling of 266401565100 in words is "two hundred sixty-six billion, four hundred one million, five hundred sixty-five thousand, one hundred".