21652743900 has 108 divisors (see below), whose sum is σ = 66119773272. Its totient is φ = 5470139520.

The previous prime is 21652743887. The next prime is 21652743901. The reversal of 21652743900 is 934725612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21652743901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 8334 + ... + 208266.

Almost surely, 2^21652743900 is an apocalyptic number.

21652743900 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21652743900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33059886636).

21652743900 is an abundant number, since it is smaller than the sum of its proper divisors (44467029372).

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

21652743900 is a wasteful number, since it uses less digits than its factorization.

21652743900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199988 (or 199962 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 39.

The spelling of 21652743900 in words is "twenty-one billion, six hundred fifty-two million, seven hundred forty-three thousand, nine hundred".