21768623360 has 144 divisors (see below), whose sum is σ = 57664837440. Its totient is φ = 7807057920.

The previous prime is 21768623351. The next prime is 21768623411. The reversal of 21768623360 is 6332686712.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1017251 + ... + 1038429.

It is an arithmetic number, because the mean of its divisors is an integer number (400450260).

Almost surely, 2^21768623360 is an apocalyptic number.

21768623360 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 21768623360, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28832418720).

21768623360 is an abundant number, since it is smaller than the sum of its proper divisors (35896214080).

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

21768623360 is a wasteful number, since it uses less digits than its factorization.

21768623360 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21284 (or 21270 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 44.

The spelling of 21768623360 in words is "twenty-one billion, seven hundred sixty-eight million, six hundred twenty-three thousand, three hundred sixty".