266640426220 has 96 divisors (see below), whose sum is σ = 650014678656. Its totient is φ = 89990400000.

The previous prime is 266640426109. The next prime is 266640426229. The reversal of 266640426220 is 22624046662.

It is a happy number.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (266640426229) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2391720 + ... + 2500720.

It is an arithmetic number, because the mean of its divisors is an integer number (6770986236).

Almost surely, 2^266640426220 is an apocalyptic number.

266640426220 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 266640426220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (325007339328).

266640426220 is an abundant number, since it is smaller than the sum of its proper divisors (383374252436).

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

266640426220 is a wasteful number, since it uses less digits than its factorization.

266640426220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109291 (or 109289 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 40.

The spelling of 266640426220 in words is "two hundred sixty-six billion, six hundred forty million, four hundred twenty-six thousand, two hundred twenty".