21283916 has 12 divisors (see below), whose sum is σ = 37291632. Its totient is φ = 10629168.

The previous prime is 21283897. The next prime is 21283919. The reversal of 21283916 is 61938212.

It is not an unprimeable number, because it can be changed into a prime (21283919) 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, 1226 + ... + 6638.

It is an arithmetic number, because the mean of its divisors is an integer number (3107636).

Almost surely, 2^21283916 is an apocalyptic number.

It is an amenable number.

21283916 is a deficient number, since it is larger than the sum of its proper divisors (16007716).

21283916 is a wasteful number, since it uses less digits than its factorization.

21283916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6400 (or 6398 counting only the distinct ones).

The product of its digits is 5184, while the sum is 32.

The square root of 21283916 is about 4613.4494686731. The cubic root of 21283916 is about 277.1301937642.

The spelling of 21283916 in words is "twenty-one million, two hundred eighty-three thousand, nine hundred sixteen".