166133021 has 8 divisors (see below), whose sum is σ = 167769888. Its totient is φ = 164502000.

The previous prime is 166133003. The next prime is 166133029. The reversal of 166133021 is 120331661.

It is a happy number.

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 166133021 - 2⁶ = 166132957 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166133029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 73691 + ... + 75911.

It is an arithmetic number, because the mean of its divisors is an integer number (20971236).

Almost surely, 2^166133021 is an apocalyptic number.

It is an amenable number.

166133021 is a deficient number, since it is larger than the sum of its proper divisors (1636867).

166133021 is a wasteful number, since it uses less digits than its factorization.

166133021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2923.

The product of its (nonzero) digits is 648, while the sum is 23.

The square root of 166133021 is about 12889.2599089319. The cubic root of 166133021 is about 549.7332270988.

Adding to 166133021 its reverse (120331661), we get a palindrome (286464682).

The spelling of 166133021 in words is "one hundred sixty-six million, one hundred thirty-three thousand, twenty-one".