166561660652 has 24 divisors (see below), whose sum is σ = 291914693616. Its totient is φ = 83157530688.

The previous prime is 166561660651. The next prime is 166561660663. The reversal of 166561660652 is 256066165661.

It is a self number, because there is not a number n which added to its sum of digits gives 166561660652.

It is not an unprimeable number, because it can be changed into a prime (166561660651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13510163 + ... + 13522485.

It is an arithmetic number, because the mean of its divisors is an integer number (12163112234).

Almost surely, 2^166561660652 is an apocalyptic number.

It is an amenable number.

166561660652 is a deficient number, since it is larger than the sum of its proper divisors (125353032964).

166561660652 is a wasteful number, since it uses less digits than its factorization.

166561660652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17057 (or 17055 counting only the distinct ones).

The product of its (nonzero) digits is 2332800, while the sum is 50.

The spelling of 166561660652 in words is "one hundred sixty-six billion, five hundred sixty-one million, six hundred sixty thousand, six hundred fifty-two".