21041304 has 16 divisors (see below), whose sum is σ = 52603320. Its totient is φ = 7013760.

The previous prime is 21041299. The next prime is 21041309. The reversal of 21041304 is 40314012.

It is an interprime number because it is at equal distance from previous prime (21041299) and next prime (21041309).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21041309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 438337 + ... + 438384.

Almost surely, 2^21041304 is an apocalyptic number.

21041304 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21041304 is an abundant number, since it is smaller than the sum of its proper divisors (31562016).

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

21041304 is a wasteful number, since it uses less digits than its factorization.

21041304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 876730 (or 876726 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 21041304 is about 4587.0801170243. The cubic root of 21041304 is about 276.0731795030.

Adding to 21041304 its reverse (40314012), we get a palindrome (61355316).

It can be divided in two parts, 210 and 41304, that added together give a palindrome (41514).

The spelling of 21041304 in words is "twenty-one million, forty-one thousand, three hundred four".