21344434 has 4 divisors (see below), whose sum is σ = 32016654. Its totient is φ = 10672216.

The previous prime is 21344419. The next prime is 21344447. The reversal of 21344434 is 43444312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 15327225 + 6017209 = 3915^2 + 2453^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21344399 and 21344408.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5336107 + ... + 5336110.

Almost surely, 2^21344434 is an apocalyptic number.

21344434 is a deficient number, since it is larger than the sum of its proper divisors (10672220).

21344434 is a wasteful number, since it uses less digits than its factorization.

21344434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10672219.

The product of its digits is 4608, while the sum is 25.

The square root of 21344434 is about 4620.0036796522. The cubic root of 21344434 is about 277.3926062264.

Adding to 21344434 its reverse (43444312), we get a palindrome (64788746).

The spelling of 21344434 in words is "twenty-one million, three hundred forty-four thousand, four hundred thirty-four".