166561856473764 has 24 divisors (see below), whose sum is σ = 389870339136768. Its totient is φ = 55345474915360.

The previous prime is 166561856473721. The next prime is 166561856473853. The reversal of 166561856473764 is 467374658165661.

166561856473764 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21892984692 + ... + 21892992299.

It is an arithmetic number, because the mean of its divisors is an integer number (16244597464032).

Almost surely, 2^{166561856473764} is an apocalyptic number.

It is an amenable number.

166561856473764 is an abundant number, since it is smaller than the sum of its proper divisors (223308482663004).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

166561856473764 is a wasteful number, since it uses less digits than its factorization.

166561856473764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43785977315 (or 43785977313 counting only the distinct ones).

The product of its digits is 3657830400, while the sum is 75.

The spelling of 166561856473764 in words is "one hundred sixty-six trillion, five hundred sixty-one billion, eight hundred fifty-six million, four hundred seventy-three thousand, seven hundred sixty-four".