21286708 has 48 divisors (see below), whose sum is σ = 40642560. Its totient is φ = 9734400.

The previous prime is 21286693. The next prime is 21286709. The reversal of 21286708 is 80768212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21286709) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 269413 + ... + 269491.

It is an arithmetic number, because the mean of its divisors is an integer number (846720).

Almost surely, 2^21286708 is an apocalyptic number.

It is an amenable number.

21286708 is a deficient number, since it is larger than the sum of its proper divisors (19355852).

21286708 is a wasteful number, since it uses less digits than its factorization.

21286708 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208 (or 206 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 34.

The square root of 21286708 is about 4613.7520522889. The cubic root of 21286708 is about 277.1423111094.

It can be divided in two parts, 2128 and 6708, that added together give a square (8836 = 94²).

The spelling of 21286708 in words is "twenty-one million, two hundred eighty-six thousand, seven hundred eight".