21051337 has 2 divisors, whose sum is σ = 21051338. Its totient is φ = 21051336.

The previous prime is 21051323. The next prime is 21051341. The reversal of 21051337 is 73315012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16679056 + 4372281 = 4084^2 + 2091^2 .

It is a cyclic number.

It is not a de Polignac number, because 21051337 - 2¹¹ = 21049289 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21051397) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10525668 + 10525669.

It is an arithmetic number, because the mean of its divisors is an integer number (10525669).

Almost surely, 2^21051337 is an apocalyptic number.

It is an amenable number.

21051337 is a deficient number, since it is larger than the sum of its proper divisors (1).

21051337 is an equidigital number, since it uses as much as digits as its factorization.

21051337 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 630, while the sum is 22.

The square root of 21051337 is about 4588.1736017723. The cubic root of 21051337 is about 276.1170519754.

Adding to 21051337 its reverse (73315012), we get a palindrome (94366349).

The spelling of 21051337 in words is "twenty-one million, fifty-one thousand, three hundred thirty-seven".