21140480 has 44 divisors (see below), whose sum is σ = 50724660. Its totient is φ = 8454144.

The previous prime is 21140423. The next prime is 21140501. The reversal of 21140480 is 8404112.

It can be written as a sum of positive squares in 2 ways, for example, as 9634816 + 11505664 = 3104^2 + 3392^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a zygodrome in base 4.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3056 + ... + 7184.

Almost surely, 2^21140480 is an apocalyptic number.

21140480 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 21140480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25362330).

21140480 is an abundant number, since it is smaller than the sum of its proper divisors (29584180).

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

21140480 is an equidigital number, since it uses as much as digits as its factorization.

21140480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4154 (or 4136 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 21140480 is about 4597.8777713202. The cubic root of 21140480 is about 276.5062472224.

Adding to 21140480 its reverse (8404112), we get a palindrome (29544592).

The spelling of 21140480 in words is "twenty-one million, one hundred forty thousand, four hundred eighty".