21428696 has 8 divisors (see below), whose sum is σ = 40178820. Its totient is φ = 10714344.

The previous prime is 21428689. The next prime is 21428699. The reversal of 21428696 is 69682412.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21428699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1339286 + ... + 1339301.

Almost surely, 2^21428696 is an apocalyptic number.

It is an amenable number.

21428696 is a deficient number, since it is larger than the sum of its proper divisors (18750124).

21428696 is a wasteful number, since it uses less digits than its factorization.

21428696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2678593 (or 2678589 counting only the distinct ones).

The product of its digits is 41472, while the sum is 38.

The square root of 21428696 is about 4629.1139540953. The cubic root of 21428696 is about 277.7571503735.

The spelling of 21428696 in words is "twenty-one million, four hundred twenty-eight thousand, six hundred ninety-six".