166100665550551 has 2 divisors, whose sum is σ = 166100665550552. Its totient is φ = 166100665550550.

The previous prime is 166100665550549. The next prime is 166100665550587. The reversal of 166100665550551 is 155055566001661.

166100665550551 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 166100665550551 - 2¹ = 166100665550549 is a prime.

Together with 166100665550549, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166100662550551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83050332775275 + 83050332775276.

It is an arithmetic number, because the mean of its divisors is an integer number (83050332775276).

Almost surely, 2^{166100665550551} is an apocalyptic number.

166100665550551 is a deficient number, since it is larger than the sum of its proper divisors (1).

166100665550551 is an equidigital number, since it uses as much as digits as its factorization.

166100665550551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4050000, while the sum is 52.

The spelling of 166100665550551 in words is "one hundred sixty-six trillion, one hundred billion, six hundred sixty-five million, five hundred fifty thousand, five hundred fifty-one".