166041021 has 8 divisors (see below), whose sum is σ = 226787904. Its totient is φ = 107994080.

The previous prime is 166041013. The next prime is 166041061. The reversal of 166041021 is 120140661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 166041021 - 2³ = 166041013 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166041061) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 674841 + ... + 675086.

It is an arithmetic number, because the mean of its divisors is an integer number (28348488).

Almost surely, 2^166041021 is an apocalyptic number.

It is an amenable number.

166041021 is a deficient number, since it is larger than the sum of its proper divisors (60746883).

166041021 is a wasteful number, since it uses less digits than its factorization.

166041021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1349971.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 166041021 is about 12885.6905519262. The cubic root of 166041021 is about 549.6317325349.

Adding to 166041021 its reverse (120140661), we get a palindrome (286181682).

The spelling of 166041021 in words is "one hundred sixty-six million, forty-one thousand, twenty-one".