21824091 has 12 divisors (see below), whose sum is σ = 32257368. Its totient is φ = 14210784.

The previous prime is 21824087. The next prime is 21824119. The reversal of 21824091 is 19042812.

It is not a de Polignac number, because 21824091 - 2² = 21824087 is a prime.

It is a super-3 number, since 3×21824091³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21824021) 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 11 ways as a sum of consecutive naturals, for example, 27810 + ... + 28583.

It is an arithmetic number, because the mean of its divisors is an integer number (2688114).

Almost surely, 2^21824091 is an apocalyptic number.

21824091 is a deficient number, since it is larger than the sum of its proper divisors (10433277).

21824091 is a wasteful number, since it uses less digits than its factorization.

21824091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56442 (or 56439 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 21824091 is about 4671.6261622694. The cubic root of 21824091 is about 279.4551095283.

The spelling of 21824091 in words is "twenty-one million, eight hundred twenty-four thousand, ninety-one".