21885038556 has 24 divisors (see below), whose sum is σ = 51192445584. Its totient is φ = 7276819200.

The previous prime is 21885038551. The next prime is 21885038579. The reversal of 21885038556 is 65583058812.

It is a junction number, because it is equal to n+sod(n) for n = 21885038499 and 21885038508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21885038551) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2269195 + ... + 2278818.

It is an arithmetic number, because the mean of its divisors is an integer number (2133018566).

Almost surely, 2^21885038556 is an apocalyptic number.

It is an amenable number.

21885038556 is an abundant number, since it is smaller than the sum of its proper divisors (29307407028).

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

21885038556 is a wasteful number, since it uses less digits than its factorization.

21885038556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4548421 (or 4548419 counting only the distinct ones).

The product of its (nonzero) digits is 2304000, while the sum is 51.

The spelling of 21885038556 in words is "twenty-one billion, eight hundred eighty-five million, thirty-eight thousand, five hundred fifty-six".