21626544436 has 24 divisors (see below), whose sum is σ = 43494736320. Its totient is φ = 9216737472.

The previous prime is 21626544391. The next prime is 21626544461. The reversal of 21626544436 is 63444562612.

It is a junction number, because it is equal to n+sod(n) for n = 21626544392 and 21626544401.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2152465 + ... + 2162488.

It is an arithmetic number, because the mean of its divisors is an integer number (1812280680).

Almost surely, 2^21626544436 is an apocalyptic number.

It is an amenable number.

21626544436 is an abundant number, since it is smaller than the sum of its proper divisors (21868191884).

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

21626544436 is a wasteful number, since it uses less digits than its factorization.

21626544436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4315143 (or 4315141 counting only the distinct ones).

The product of its digits is 829440, while the sum is 43.

The spelling of 21626544436 in words is "twenty-one billion, six hundred twenty-six million, five hundred forty-four thousand, four hundred thirty-six".