20661206147 has 2 divisors, whose sum is σ = 20661206148. Its totient is φ = 20661206146.

The previous prime is 20661206057. The next prime is 20661206183. The reversal of 20661206147 is 74160216602.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20661206147 is a prime.

It is not a weakly prime, because it can be changed into another prime (20661206197) 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, 10330603073 + 10330603074.

It is an arithmetic number, because the mean of its divisors is an integer number (10330603074).

Almost surely, 2^20661206147 is an apocalyptic number.

20661206147 is a deficient number, since it is larger than the sum of its proper divisors (1).

20661206147 is an equidigital number, since it uses as much as digits as its factorization.

20661206147 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 24192, while the sum is 35.

The spelling of 20661206147 in words is "twenty billion, six hundred sixty-one million, two hundred six thousand, one hundred forty-seven".