21283072 has 18 divisors (see below), whose sum is σ = 42483518. Its totient is φ = 10641408.

The previous prime is 21283039. The next prime is 21283091. The reversal of 21283072 is 27038212.

It can be written as a sum of positive squares in only one way, i.e., 11943936 + 9339136 = 3456^2 + 3056^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41313 + ... + 41824.

Almost surely, 2^21283072 is an apocalyptic number.

It is an amenable number.

21283072 is a deficient number, since it is larger than the sum of its proper divisors (21200446).

21283072 is an frugal number, since it uses more digits than its factorization.

21283072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83153 (or 83139 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 25.

The square root of 21283072 is about 4613.3579960805. The cubic root of 21283072 is about 277.1265305759.

The spelling of 21283072 in words is "twenty-one million, two hundred eighty-three thousand, seventy-two".