21118460 has 48 divisors (see below), whose sum is σ = 49230720. Its totient is φ = 7544640.

The previous prime is 21118441. The next prime is 21118501. The reversal of 21118460 is 6481112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12167 + ... + 13793.

It is an arithmetic number, because the mean of its divisors is an integer number (1025640).

Almost surely, 2^21118460 is an apocalyptic number.

21118460 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 21118460, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24615360).

21118460 is an abundant number, since it is smaller than the sum of its proper divisors (28112260).

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

21118460 is a wasteful number, since it uses less digits than its factorization.

21118460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1706 (or 1704 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 23.

The square root of 21118460 is about 4595.4825644322. The cubic root of 21118460 is about 276.4102105701.

Adding to 21118460 its reverse (6481112), we get a palindrome (27599572).

The spelling of 21118460 in words is "twenty-one million, one hundred eighteen thousand, four hundred sixty".