21055260 has 48 divisors (see below), whose sum is σ = 59544576. Its totient is φ = 5558592.

The previous prime is 21055259. The next prime is 21055261. The reversal of 21055260 is 6255012.

21055260 is nontrivially palindromic in base 14.

It is an interprime number because it is at equal distance from previous prime (21055259) and next prime (21055261).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21055261) 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, 4477 + ... + 7883.

It is an arithmetic number, because the mean of its divisors is an integer number (1240512).

Almost surely, 2^21055260 is an apocalyptic number.

21055260 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 21055260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29772288).

21055260 is an abundant number, since it is smaller than the sum of its proper divisors (38489316).

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

21055260 is a wasteful number, since it uses less digits than its factorization.

21055260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3522 (or 3520 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 21055260 is about 4588.6010940155. The cubic root of 21055260 is about 276.1342027454.

The spelling of 21055260 in words is "twenty-one million, fifty-five thousand, two hundred sixty".