20640000617 has 2 divisors, whose sum is σ = 20640000618. Its totient is φ = 20640000616.

The previous prime is 20640000583. The next prime is 20640000683. The reversal of 20640000617 is 71600004602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15499254016 + 5140746601 = 124496^2 + 71699^2 .

It is a cyclic number.

It is not a de Polignac number, because 20640000617 - 2¹² = 20639996521 is a prime.

It is not a weakly prime, because it can be changed into another prime (20640000517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10320000308 + 10320000309.

It is an arithmetic number, because the mean of its divisors is an integer number (10320000309).

Almost surely, 2^20640000617 is an apocalyptic number.

It is an amenable number.

20640000617 is a deficient number, since it is larger than the sum of its proper divisors (1).

20640000617 is an equidigital number, since it uses as much as digits as its factorization.

20640000617 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 26.

The spelling of 20640000617 in words is "twenty billion, six hundred forty million, six hundred seventeen", and thus it is an aban number.