21188754552 has 128 divisors (see below), whose sum is σ = 64770854400. Its totient is φ = 5641228800.

The previous prime is 21188754539. The next prime is 21188754553. The reversal of 21188754552 is 25545788112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21188754553) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 140302 + ... + 249122.

It is an arithmetic number, because the mean of its divisors is an integer number (506022300).

Almost surely, 2^21188754552 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21188754552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32385427200).

21188754552 is an abundant number, since it is smaller than the sum of its proper divisors (43582099848).

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

21188754552 is a wasteful number, since it uses less digits than its factorization.

21188754552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108917 (or 108913 counting only the distinct ones).

The product of its digits is 896000, while the sum is 48.

The spelling of 21188754552 in words is "twenty-one billion, one hundred eighty-eight million, seven hundred fifty-four thousand, five hundred fifty-two".