166681456925 has 12 divisors (see below), whose sum is σ = 206789824500. Its totient is φ = 133277541120.

The previous prime is 166681456889. The next prime is 166681456927. The reversal of 166681456925 is 529654186661.

It can be written as a sum of positive squares in 6 ways, for example, as 8606829529 + 158074627396 = 92773^2 + 397586^2 .

It is not a de Polignac number, because 166681456925 - 2²⁸ = 166413021469 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166681456927) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1640300 + ... + 1738949.

It is an arithmetic number, because the mean of its divisors is an integer number (17232485375).

Almost surely, 2^166681456925 is an apocalyptic number.

It is an amenable number.

166681456925 is a deficient number, since it is larger than the sum of its proper divisors (40108367575).

166681456925 is a wasteful number, since it uses less digits than its factorization.

166681456925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3381232 (or 3381227 counting only the distinct ones).

The product of its digits is 18662400, while the sum is 59.

The spelling of 166681456925 in words is "one hundred sixty-six billion, six hundred eighty-one million, four hundred fifty-six thousand, nine hundred twenty-five".