166121205 has 16 divisors (see below), whose sum is σ = 265997760. Its totient is φ = 88530048.

The previous prime is 166121191. The next prime is 166121213. The reversal of 166121205 is 502121661.

It is not a de Polignac number, because 166121205 - 2⁶ = 166121141 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20694 + ... + 27576.

It is an arithmetic number, because the mean of its divisors is an integer number (16624860).

Almost surely, 2^166121205 is an apocalyptic number.

166121205 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

166121205 is a deficient number, since it is larger than the sum of its proper divisors (99876555).

166121205 is a wasteful number, since it uses less digits than its factorization.

166121205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8500.

The product of its (nonzero) digits is 720, while the sum is 24.

The square root of 166121205 is about 12888.8015346657. The cubic root of 166121205 is about 549.7201937641.

Adding to 166121205 its reverse (502121661), we get a palindrome (668242866).

The spelling of 166121205 in words is "one hundred sixty-six million, one hundred twenty-one thousand, two hundred five".