21650546560 has 64 divisors (see below), whose sum is σ = 51796889280. Its totient is φ = 8653768704.

The previous prime is 21650546549. The next prime is 21650546563. The reversal of 21650546560 is 6564505612.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21650546563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 898834 + ... + 922606.

It is an arithmetic number, because the mean of its divisors is an integer number (809326395).

Almost surely, 2^21650546560 is an apocalyptic number.

21650546560 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 21650546560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25898444640).

21650546560 is an abundant number, since it is smaller than the sum of its proper divisors (30146342720).

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

21650546560 is a wasteful number, since it uses less digits than its factorization.

21650546560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25215 (or 25203 counting only the distinct ones).

The product of its (nonzero) digits is 216000, while the sum is 40.

The spelling of 21650546560 in words is "twenty-one billion, six hundred fifty million, five hundred forty-six thousand, five hundred sixty".