20875638947 has 2 divisors, whose sum is σ = 20875638948. Its totient is φ = 20875638946.

The previous prime is 20875638923. The next prime is 20875638977. The reversal of 20875638947 is 74983657802.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20875638947 - 2²⁰ = 20874590371 is a prime.

It is not a weakly prime, because it can be changed into another prime (20875638977) 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, 10437819473 + 10437819474.

It is an arithmetic number, because the mean of its divisors is an integer number (10437819474).

Almost surely, 2^20875638947 is an apocalyptic number.

20875638947 is a deficient number, since it is larger than the sum of its proper divisors (1).

20875638947 is an equidigital number, since it uses as much as digits as its factorization.

20875638947 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20321280, while the sum is 59.

The spelling of 20875638947 in words is "twenty billion, eight hundred seventy-five million, six hundred thirty-eight thousand, nine hundred forty-seven".