21283772 has 12 divisors (see below), whose sum is σ = 37519440. Its totient is φ = 10563936.

The previous prime is 21283771. The next prime is 21283777. The reversal of 21283772 is 27738212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21283771) 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, 18872 + ... + 19967.

It is an arithmetic number, because the mean of its divisors is an integer number (3126620).

Almost surely, 2^21283772 is an apocalyptic number.

It is an amenable number.

21283772 is a deficient number, since it is larger than the sum of its proper divisors (16235668).

21283772 is a wasteful number, since it uses less digits than its factorization.

21283772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38980 (or 38978 counting only the distinct ones).

The product of its digits is 9408, while the sum is 32.

The square root of 21283772 is about 4613.4338621032. The cubic root of 21283772 is about 277.1295687721.

The spelling of 21283772 in words is "twenty-one million, two hundred eighty-three thousand, seven hundred seventy-two".