21169128960 has 720 divisors, whose sum is σ = 90382982976. Its totient is φ = 4549902336.

The previous prime is 21169128941. The next prime is 21169128997. The reversal of 21169128960 is 6982196112.

It is a tau number, because it is divible by the number of its divisors (720).

It is a super-2 number, since 2×21169128960² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 19191769 + ... + 19192871.

Almost surely, 2^21169128960 is an apocalyptic number.

21169128960 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 21169128960, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45191491488).

21169128960 is an abundant number, since it is smaller than the sum of its proper divisors (69213854016).

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

21169128960 is a wasteful number, since it uses less digits than its factorization.

21169128960 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1163 (or 1137 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 45.

The spelling of 21169128960 in words is "twenty-one billion, one hundred sixty-nine million, one hundred twenty-eight thousand, nine hundred sixty".