21280802160 has 80 divisors (see below), whose sum is σ = 66061771776. Its totient is φ = 5667028224.

The previous prime is 21280802119. The next prime is 21280802167. The reversal of 21280802160 is 6120808212.

It is a tau number, because it is divible by the number of its divisors (80).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21280802167) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 113497 + ... + 235463.

Almost surely, 2^21280802160 is an apocalyptic number.

21280802160 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 21280802160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33030885888).

21280802160 is an abundant number, since it is smaller than the sum of its proper divisors (44780969616).

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

21280802160 is a wasteful number, since it uses less digits than its factorization.

21280802160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122710 (or 122704 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 30.

The spelling of 21280802160 in words is "twenty-one billion, two hundred eighty million, eight hundred two thousand, one hundred sixty".