21265460 has 12 divisors (see below), whose sum is σ = 44657508. Its totient is φ = 8506176.

The previous prime is 21265459. The next prime is 21265523. The reversal of 21265460 is 6456212.

It can be written as a sum of positive squares in 2 ways, for example, as 8832784 + 12432676 = 2972^2 + 3526^2 .

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 3 ways as a sum of consecutive naturals, for example, 531617 + ... + 531656.

It is an arithmetic number, because the mean of its divisors is an integer number (3721459).

Almost surely, 2^21265460 is an apocalyptic number.

21265460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21265460 is an abundant number, since it is smaller than the sum of its proper divisors (23392048).

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

21265460 is a wasteful number, since it uses less digits than its factorization.

21265460 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1063282 (or 1063280 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 21265460 is about 4611.4487962028. The cubic root of 21265460 is about 277.0500676265.

The spelling of 21265460 in words is "twenty-one million, two hundred sixty-five thousand, four hundred sixty".