21311744160 has 192 divisors, whose sum is σ = 77239008000. Its totient is φ = 4838449152.

The previous prime is 21311744159. The next prime is 21311744171. The reversal of 21311744160 is 6144711312.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 479356 + ... + 521924.

It is an arithmetic number, because the mean of its divisors is an integer number (402286500).

Almost surely, 2^21311744160 is an apocalyptic number.

21311744160 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 21311744160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38619504000).

21311744160 is an abundant number, since it is smaller than the sum of its proper divisors (55927263840).

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

21311744160 is a wasteful number, since it uses less digits than its factorization.

21311744160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42743 (or 42735 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 30.

The spelling of 21311744160 in words is "twenty-one billion, three hundred eleven million, seven hundred forty-four thousand, one hundred sixty".