21440131266 has 16 divisors (see below), whose sum is σ = 42941441088. Its totient is φ = 7136514000.

The previous prime is 21440131243. The next prime is 21440131289. The reversal of 21440131266 is 66213104412.

It is an interprime number because it is at equal distance from previous prime (21440131243) and next prime (21440131289).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2544550 + ... + 2552961.

It is an arithmetic number, because the mean of its divisors is an integer number (2683840068).

Almost surely, 2^21440131266 is an apocalyptic number.

21440131266 is an abundant number, since it is smaller than the sum of its proper divisors (21501309822).

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

21440131266 is a wasteful number, since it uses less digits than its factorization.

21440131266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5098217.

The product of its (nonzero) digits is 6912, while the sum is 30.

Adding to 21440131266 its reverse (66213104412), we get a palindrome (87653235678).

The spelling of 21440131266 in words is "twenty-one billion, four hundred forty million, one hundred thirty-one thousand, two hundred sixty-six".