21843413 has 4 divisors (see below), whose sum is σ = 21924288. Its totient is φ = 21762540.

The previous prime is 21843403. The next prime is 21843427. The reversal of 21843413 is 31434812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21843413 - 2⁴ = 21843397 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21843403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40031 + ... + 40572.

It is an arithmetic number, because the mean of its divisors is an integer number (5481072).

Almost surely, 2^21843413 is an apocalyptic number.

It is an amenable number.

21843413 is a deficient number, since it is larger than the sum of its proper divisors (80875).

21843413 is an equidigital number, since it uses as much as digits as its factorization.

21843413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80874.

The product of its digits is 2304, while the sum is 26.

The square root of 21843413 is about 4673.6937212445. The cubic root of 21843413 is about 279.5375572369.

The spelling of 21843413 in words is "twenty-one million, eight hundred forty-three thousand, four hundred thirteen".