20472557166577 has 2 divisors, whose sum is σ = 20472557166578. Its totient is φ = 20472557166576.

The previous prime is 20472557166533. The next prime is 20472557166637. The reversal of 20472557166577 is 77566175527402.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18876279059856 + 1596278106721 = 4344684^2 + 1263439^2 .

It is a cyclic number.

It is not a de Polignac number, because 20472557166577 - 2³⁹ = 19922801352689 is a prime.

It is not a weakly prime, because it can be changed into another prime (20472557166517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10236278583288 + 10236278583289.

It is an arithmetic number, because the mean of its divisors is an integer number (10236278583289).

Almost surely, 2^{20472557166577} is an apocalyptic number.

It is an amenable number.

20472557166577 is a deficient number, since it is larger than the sum of its proper divisors (1).

20472557166577 is an equidigital number, since it uses as much as digits as its factorization.

20472557166577 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 172872000, while the sum is 64.

The spelling of 20472557166577 in words is "twenty trillion, four hundred seventy-two billion, five hundred fifty-seven million, one hundred sixty-six thousand, five hundred seventy-seven".