21439814 has 8 divisors (see below), whose sum is σ = 35083368. Its totient is φ = 9745360.

The previous prime is 21439807. The next prime is 21439823. The reversal of 21439814 is 41893412.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

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 in 3 ways as a sum of consecutive naturals, for example, 487247 + ... + 487290.

It is an arithmetic number, because the mean of its divisors is an integer number (4385421).

Almost surely, 2^21439814 is an apocalyptic number.

21439814 is a deficient number, since it is larger than the sum of its proper divisors (13643554).

21439814 is a wasteful number, since it uses less digits than its factorization.

21439814 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 974550.

The product of its digits is 6912, while the sum is 32.

The square root of 21439814 is about 4630.3146761316. The cubic root of 21439814 is about 277.8051789621.

It can be divided in two parts, 214398 and 14, that added together give a palindrome (214412).

The spelling of 21439814 in words is "twenty-one million, four hundred thirty-nine thousand, eight hundred fourteen".