21101080 has 256 divisors, whose sum is σ = 69672960. Its totient is φ = 5529600.

The previous prime is 21101033. The next prime is 21101123. The reversal of 21101080 is 8010112.

21101080 is nontrivially palindromic in base 3.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a self number, because there is not a number n which added to its sum of digits gives 21101080.

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 63 ways as a sum of consecutive naturals, for example, 680665 + ... + 680695.

It is an arithmetic number, because the mean of its divisors is an integer number (272160).

Almost surely, 2^21101080 is an apocalyptic number.

21101080 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 21101080, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34836480).

21101080 is an abundant number, since it is smaller than the sum of its proper divisors (48571880).

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

21101080 is a wasteful number, since it uses less digits than its factorization.

21101080 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90 (or 86 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 21101080 is about 4593.5911877310. The cubic root of 21101080 is about 276.3343633741.

Adding to 21101080 its reverse (8010112), we get a palindrome (29111192).

It can be divided in two parts, 21 and 101080, that added together give a palindrome (101101).

The spelling of 21101080 in words is "twenty-one million, one hundred one thousand, eighty".