26855122221 has 24 divisors (see below), whose sum is σ = 39956487480. Its totient is φ = 17370201600.

The previous prime is 26855122219. The next prime is 26855122267. The reversal of 26855122221 is 12222155862.

26855122221 is a `hidden beast` number, since 2 + 68 + 551 + 2 + 22 + 21 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 62015625 + 26793106596 = 7875^2 + 163686^2 .

It is not a de Polignac number, because 26855122221 - 2¹ = 26855122219 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26855122421) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 134256 + ... + 267833.

It is an arithmetic number, because the mean of its divisors is an integer number (1664853645).

Almost surely, 2^26855122221 is an apocalyptic number.

It is an amenable number.

26855122221 is a deficient number, since it is larger than the sum of its proper divisors (13101365259).

26855122221 is a wasteful number, since it uses less digits than its factorization.

26855122221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 402317 (or 402314 counting only the distinct ones).

The product of its digits is 38400, while the sum is 36.

The spelling of 26855122221 in words is "twenty-six billion, eight hundred fifty-five million, one hundred twenty-two thousand, two hundred twenty-one".