20622661 has 2 divisors, whose sum is σ = 20622662. Its totient is φ = 20622660.

The previous prime is 20622647. The next prime is 20622673. The reversal of 20622661 is 16622602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20520900 + 101761 = 4530^2 + 319^2 .

It is a cyclic number.

It is not a de Polignac number, because 20622661 - 2⁹ = 20622149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20622601) 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, 10311330 + 10311331.

It is an arithmetic number, because the mean of its divisors is an integer number (10311331).

Almost surely, 2^20622661 is an apocalyptic number.

It is an amenable number.

20622661 is a deficient number, since it is larger than the sum of its proper divisors (1).

20622661 is an equidigital number, since it uses as much as digits as its factorization.

20622661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 20622661 is about 4541.2180084202. The cubic root of 20622661 is about 274.2299603913.

The spelling of 20622661 in words is "twenty million, six hundred twenty-two thousand, six hundred sixty-one".