21168441 has 36 divisors (see below), whose sum is σ = 37132992. Its totient is φ = 11564784.

The previous prime is 21168439. The next prime is 21168461. The reversal of 21168441 is 14486112.

It is a happy number.

21168441 is a `hidden beast` number, since 211 + 6 + 8 + 441 = 666.

It is not a de Polignac number, because 21168441 - 2¹ = 21168439 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21168461) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 9100 + ... + 11186.

It is an arithmetic number, because the mean of its divisors is an integer number (1031472).

Almost surely, 2^21168441 is an apocalyptic number.

21168441 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21168441 is a deficient number, since it is larger than the sum of its proper divisors (15964551).

21168441 is a wasteful number, since it uses less digits than its factorization.

21168441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2130 (or 2120 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 21168441 is about 4600.9174085176. The cubic root of 21168441 is about 276.6280985253.

It can be divided in two parts, 21168 and 441, that added together give a square (21609 = 147²).

The spelling of 21168441 in words is "twenty-one million, one hundred sixty-eight thousand, four hundred forty-one".