166121425 has 12 divisors (see below), whose sum is σ = 213094620. Its totient is φ = 128313920.

The previous prime is 166121411. The next prime is 166121443. The reversal of 166121425 is 524121661.

It can be written as a sum of positive squares in 6 ways, for example, as 11566801 + 154554624 = 3401^2 + 12432^2 .

It is not a de Polignac number, because 166121425 - 2⁵ = 166121393 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 166121393 and 166121402.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 113842 + ... + 115291.

It is an arithmetic number, because the mean of its divisors is an integer number (17757885).

Almost surely, 2^166121425 is an apocalyptic number.

It is an amenable number.

166121425 is a deficient number, since it is larger than the sum of its proper divisors (46973195).

166121425 is a wasteful number, since it uses less digits than its factorization.

166121425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229172 (or 229167 counting only the distinct ones).

The product of its digits is 2880, while the sum is 28.

The square root of 166121425 is about 12888.8100692034. The cubic root of 166121425 is about 549.7204364350.

The spelling of 166121425 in words is "one hundred sixty-six million, one hundred twenty-one thousand, four hundred twenty-five".