166561560014425 has 6 divisors (see below), whose sum is σ = 206536334417918. Its totient is φ = 133249248011520.

The previous prime is 166561560014411. The next prime is 166561560014429. The reversal of 166561560014425 is 524410065165661.

It can be written as a sum of positive squares in 3 ways, for example, as 168897162841 + 166392662851584 = 410971^2 + 12899328^2 .

It is not a de Polignac number, because 166561560014425 - 2¹⁷ = 166561559883353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (166561560014429) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3331231200264 + ... + 3331231200313.

Almost surely, 2^{166561560014425} is an apocalyptic number.

It is an amenable number.

166561560014425 is a deficient number, since it is larger than the sum of its proper divisors (39974774403493).

166561560014425 is an equidigital number, since it uses as much as digits as its factorization.

166561560014425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6662462400587 (or 6662462400582 counting only the distinct ones).

The product of its (nonzero) digits is 5184000, while the sum is 52.

The spelling of 166561560014425 in words is "one hundred sixty-six trillion, five hundred sixty-one billion, five hundred sixty million, fourteen thousand, four hundred twenty-five".