21283297 has 6 divisors (see below), whose sum is σ = 24758178. Its totient is φ = 18242784.

The previous prime is 21283291. The next prime is 21283307. The reversal of 21283297 is 79238212.

It can be written as a sum of positive squares in only one way, i.e., 21150801 + 132496 = 4599^2 + 364^2 .

It is not a de Polignac number, because 21283297 - 2⁷ = 21283169 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21283291) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 217128 + ... + 217225.

It is an arithmetic number, because the mean of its divisors is an integer number (4126363).

Almost surely, 2^21283297 is an apocalyptic number.

It is an amenable number.

21283297 is a deficient number, since it is larger than the sum of its proper divisors (3474881).

21283297 is an equidigital number, since it uses as much as digits as its factorization.

21283297 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434367 (or 434360 counting only the distinct ones).

The product of its digits is 12096, while the sum is 34.

The square root of 21283297 is about 4613.3823817238. The cubic root of 21283297 is about 277.1275071462.

The spelling of 21283297 in words is "twenty-one million, two hundred eighty-three thousand, two hundred ninety-seven".