21447113 has 4 divisors (see below), whose sum is σ = 21505920. Its totient is φ = 21388308.

The previous prime is 21447091. The next prime is 21447119. The reversal of 21447113 is 31174412.

It is a happy number.

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 21447113 - 2⁸ = 21446857 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (21447119) 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 3 ways as a sum of consecutive naturals, for example, 28853 + ... + 29586.

It is an arithmetic number, because the mean of its divisors is an integer number (5376480).

Almost surely, 2^21447113 is an apocalyptic number.

It is an amenable number.

21447113 is a deficient number, since it is larger than the sum of its proper divisors (58807).

21447113 is an equidigital number, since it uses as much as digits as its factorization.

21447113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58806.

The product of its digits is 672, while the sum is 23.

The square root of 21447113 is about 4631.1027844348. The cubic root of 21447113 is about 277.8367008454.

The spelling of 21447113 in words is "twenty-one million, four hundred forty-seven thousand, one hundred thirteen".