20564147 has 2 divisors, whose sum is σ = 20564148. Its totient is φ = 20564146.

The previous prime is 20564123. The next prime is 20564171. The reversal of 20564147 is 74146502.

It is a balanced prime because it is at equal distance from previous prime (20564123) and next prime (20564171).

It is a cyclic number.

It is not a de Polignac number, because 20564147 - 2⁸ = 20563891 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20564177) 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, 10282073 + 10282074.

It is an arithmetic number, because the mean of its divisors is an integer number (10282074).

Almost surely, 2^20564147 is an apocalyptic number.

20564147 is a deficient number, since it is larger than the sum of its proper divisors (1).

20564147 is an equidigital number, since it uses as much as digits as its factorization.

20564147 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 29.

The square root of 20564147 is about 4534.7708872665. The cubic root of 20564147 is about 273.9703512771.

The spelling of 20564147 in words is "twenty million, five hundred sixty-four thousand, one hundred forty-seven".