22051661 has 2 divisors, whose sum is σ = 22051662. Its totient is φ = 22051660.

The previous prime is 22051651. The next prime is 22051709. The reversal of 22051661 is 16615022.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11095561 + 10956100 = 3331^2 + 3310^2 .

It is a cyclic number.

It is not a de Polignac number, because 22051661 - 2⁶ = 22051597 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22051651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11025830 + 11025831.

It is an arithmetic number, because the mean of its divisors is an integer number (11025831).

Almost surely, 2^22051661 is an apocalyptic number.

It is an amenable number.

22051661 is a deficient number, since it is larger than the sum of its proper divisors (1).

22051661 is an equidigital number, since it uses as much as digits as its factorization.

22051661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 22051661 is about 4695.9196117481. The cubic root of 22051661 is about 280.4230891181.

Adding to 22051661 its reverse (16615022), we get a palindrome (38666683).

The spelling of 22051661 in words is "twenty-two million, fifty-one thousand, six hundred sixty-one".