21270480 has 160 divisors (see below), whose sum is σ = 82280448. Its totient is φ = 4416000.

The previous prime is 21270439. The next prime is 21270511. The reversal of 21270480 is 8407212.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 21270480.

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 31 ways as a sum of consecutive naturals, for example, 17905 + ... + 19055.

Almost surely, 2^21270480 is an apocalyptic number.

21270480 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 21270480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41140224).

21270480 is an abundant number, since it is smaller than the sum of its proper divisors (61009968).

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

21270480 is a wasteful number, since it uses less digits than its factorization.

21270480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1185 (or 1179 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 24.

The square root of 21270480 is about 4611.9930615733. The cubic root of 21270480 is about 277.0718663856.

Adding to 21270480 its reverse (8407212), we get a palindrome (29677692).

The spelling of 21270480 in words is "twenty-one million, two hundred seventy thousand, four hundred eighty".