21104493 has 16 divisors (see below), whose sum is σ = 28740096. Its totient is φ = 13772720.

The previous prime is 21104491. The next prime is 21104507. The reversal of 21104493 is 39440112.

It is a cyclic number.

It is not a de Polignac number, because 21104493 - 2¹ = 21104491 is a prime.

It is a super-3 number, since 3×21104493³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21104491) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 32296 + ... + 32942.

It is an arithmetic number, because the mean of its divisors is an integer number (1796256).

Almost surely, 2^21104493 is an apocalyptic number.

It is an amenable number.

21104493 is a deficient number, since it is larger than the sum of its proper divisors (7635603).

21104493 is a wasteful number, since it uses less digits than its factorization.

21104493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 864.

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 21104493 is about 4593.9626685466. The cubic root of 21104493 is about 276.3492611635.

The spelling of 21104493 in words is "twenty-one million, one hundred four thousand, four hundred ninety-three".