21344873 has 4 divisors (see below), whose sum is σ = 23285328. Its totient is φ = 19404420.

The previous prime is 21344857. The next prime is 21344903. The reversal of 21344873 is 37844312.

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 21344873 - 2⁴ = 21344857 is a prime.

It is a super-2 number, since 2×21344873² = 911207206772258, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21344803) 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, 970211 + ... + 970232.

It is an arithmetic number, because the mean of its divisors is an integer number (5821332).

Almost surely, 2^21344873 is an apocalyptic number.

It is an amenable number.

21344873 is a deficient number, since it is larger than the sum of its proper divisors (1940455).

21344873 is a wasteful number, since it uses less digits than its factorization.

21344873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1940454.

The product of its digits is 16128, while the sum is 32.

The square root of 21344873 is about 4620.0511901926. The cubic root of 21344873 is about 277.3945079637.

It can be divided in two parts, 2134 and 4873, that added together give a palindrome (7007).

The spelling of 21344873 in words is "twenty-one million, three hundred forty-four thousand, eight hundred seventy-three".