21250337 has 2 divisors, whose sum is σ = 21250338. Its totient is φ = 21250336.

The previous prime is 21250331. The next prime is 21250351. The reversal of 21250337 is 73305212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21077281 + 173056 = 4591^2 + 416^2 .

It is a cyclic number.

It is not a de Polignac number, because 21250337 - 2¹⁰ = 21249313 is a prime.

It is a super-2 number, since 2×21250337² = 903153645227138, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21250331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10625168 + 10625169.

It is an arithmetic number, because the mean of its divisors is an integer number (10625169).

Almost surely, 2^21250337 is an apocalyptic number.

It is an amenable number.

21250337 is a deficient number, since it is larger than the sum of its proper divisors (1).

21250337 is an equidigital number, since it uses as much as digits as its factorization.

21250337 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1260, while the sum is 23.

The square root of 21250337 is about 4609.8087812837. The cubic root of 21250337 is about 276.9843770377.

Adding to 21250337 its reverse (73305212), we get a palindrome (94555549).

The spelling of 21250337 in words is "twenty-one million, two hundred fifty thousand, three hundred thirty-seven".