21260424 has 32 divisors (see below), whose sum is σ = 53269920. Its totient is φ = 7070976.

The previous prime is 21260419. The next prime is 21260429. The reversal of 21260424 is 42406212.

It is an interprime number because it is at equal distance from previous prime (21260419) and next prime (21260429).

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 21260424.

It is not an unprimeable number, because it can be changed into a prime (21260429) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15744 + ... + 17040.

It is an arithmetic number, because the mean of its divisors is an integer number (1664685).

Almost surely, 2^21260424 is an apocalyptic number.

21260424 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21260424 is an abundant number, since it is smaller than the sum of its proper divisors (32009496).

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

21260424 is a wasteful number, since it uses less digits than its factorization.

21260424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1989 (or 1985 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 21260424 is about 4610.9027315700. The cubic root of 21260424 is about 277.0281959421.

Adding to 21260424 its reverse (42406212), we get a palindrome (63666636).

The spelling of 21260424 in words is "twenty-one million, two hundred sixty thousand, four hundred twenty-four".