21104451 has 6 divisors (see below), whose sum is σ = 30484220. Its totient is φ = 14069628.

The previous prime is 21104407. The next prime is 21104453. The reversal of 21104451 is 15440112.

21104451 is a `hidden beast` number, since 211 + 0 + 4 + 451 = 666.

It is not a de Polignac number, because 21104451 - 2⁷ = 21104323 is a prime.

It is a super-2 number, since 2×21104451² = 890795704022802, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21104453) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1172461 + ... + 1172478.

Almost surely, 2^21104451 is an apocalyptic number.

21104451 is a deficient number, since it is larger than the sum of its proper divisors (9379769).

21104451 is a wasteful number, since it uses less digits than its factorization.

21104451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2344945 (or 2344942 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 21104451 is about 4593.9580973274. The cubic root of 21104451 is about 276.3490778427.

Adding to 21104451 its reverse (15440112), we get a palindrome (36544563).

It can be divided in two parts, 2110 and 4451, that added together give a 8-th power (6561 = 3⁸).

The spelling of 21104451 in words is "twenty-one million, one hundred four thousand, four hundred fifty-one".