21688266744 has 48 divisors (see below), whose sum is σ = 59161666200. Its totient is φ = 7177408704.

The previous prime is 21688266739. The next prime is 21688266757. The reversal of 21688266744 is 44766288612.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1073539 + ... + 1093554.

Almost surely, 2^21688266744 is an apocalyptic number.

21688266744 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21688266744 is an abundant number, since it is smaller than the sum of its proper divisors (37473399456).

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

21688266744 is a wasteful number, since it uses less digits than its factorization.

21688266744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2167244 (or 2167237 counting only the distinct ones).

The product of its digits is 6193152, while the sum is 54.

The spelling of 21688266744 in words is "twenty-one billion, six hundred eighty-eight million, two hundred sixty-six thousand, seven hundred forty-four".