21439696 has 20 divisors (see below), whose sum is σ = 41729472. Its totient is φ = 10670816.

The previous prime is 21439673. The next prime is 21439699. The reversal of 21439696 is 69693412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21439699) 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, 681 + ... + 6583.

Almost surely, 2^21439696 is an apocalyptic number.

It is an amenable number.

21439696 is a deficient number, since it is larger than the sum of its proper divisors (20289776).

21439696 is a wasteful number, since it uses less digits than its factorization.

21439696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6138 (or 6132 counting only the distinct ones).

The product of its digits is 69984, while the sum is 40.

The square root of 21439696 is about 4630.3019339996. The cubic root of 21439696 is about 277.8046693017.

The spelling of 21439696 in words is "twenty-one million, four hundred thirty-nine thousand, six hundred ninety-six".