21283516 has 6 divisors (see below), whose sum is σ = 37246160. Its totient is φ = 10641756.

The previous prime is 21283513. The next prime is 21283517. The reversal of 21283516 is 61538212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21283511) by changing a digit.

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, 2660436 + ... + 2660443.

Almost surely, 2^21283516 is an apocalyptic number.

It is an amenable number.

21283516 is a deficient number, since it is larger than the sum of its proper divisors (15962644).

21283516 is a wasteful number, since it uses less digits than its factorization.

21283516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5320883 (or 5320881 counting only the distinct ones).

The product of its digits is 2880, while the sum is 28.

The square root of 21283516 is about 4613.4061169596. The cubic root of 21283516 is about 277.1284576681.

The spelling of 21283516 in words is "twenty-one million, two hundred eighty-three thousand, five hundred sixteen".