21993341 has 2 divisors, whose sum is σ = 21993342. Its totient is φ = 21993340.

The previous prime is 21993319. The next prime is 21993347. The reversal of 21993341 is 14339912.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21576025 + 417316 = 4645^2 + 646^2 .

It is a cyclic number.

It is not a de Polignac number, because 21993341 - 2¹⁰ = 21992317 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21993298 and 21993307.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21993347) 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, 10996670 + 10996671.

It is an arithmetic number, because the mean of its divisors is an integer number (10996671).

Almost surely, 2^21993341 is an apocalyptic number.

It is an amenable number.

21993341 is a deficient number, since it is larger than the sum of its proper divisors (1).

21993341 is an equidigital number, since it uses as much as digits as its factorization.

21993341 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5832, while the sum is 32.

The square root of 21993341 is about 4689.7058543154. The cubic root of 21993341 is about 280.1756593341.

The spelling of 21993341 in words is "twenty-one million, nine hundred ninety-three thousand, three hundred forty-one".