21753337 has 2 divisors, whose sum is σ = 21753338. Its totient is φ = 21753336.

The previous prime is 21753311. The next prime is 21753341. The reversal of 21753337 is 73335712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21752896 + 441 = 4664^2 + 21^2 .

It is a cyclic number.

It is not a de Polignac number, because 21753337 - 2⁷ = 21753209 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21753299 and 21753308.

It is not a weakly prime, because it can be changed into another prime (21753367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10876668 + 10876669.

It is an arithmetic number, because the mean of its divisors is an integer number (10876669).

Almost surely, 2^21753337 is an apocalyptic number.

It is an amenable number.

21753337 is a deficient number, since it is larger than the sum of its proper divisors (1).

21753337 is an equidigital number, since it uses as much as digits as its factorization.

21753337 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13230, while the sum is 31.

The square root of 21753337 is about 4664.0472767758. The cubic root of 21753337 is about 279.1527834882.

The spelling of 21753337 in words is "twenty-one million, seven hundred fifty-three thousand, three hundred thirty-seven".