166122021 has 16 divisors (see below), whose sum is σ = 238809536. Its totient is φ = 102110976.

The previous prime is 166122013. The next prime is 166122041. The reversal of 166122021 is 120221661.

166122021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 166122021 - 2³ = 166122013 is a prime.

It is a super-2 number, since 2×166122021² = 55193051722248882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166122041) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41901 + ... + 45693.

It is an arithmetic number, because the mean of its divisors is an integer number (14925596).

Almost surely, 2^166122021 is an apocalyptic number.

It is an amenable number.

166122021 is a deficient number, since it is larger than the sum of its proper divisors (72687515).

166122021 is a wasteful number, since it uses less digits than its factorization.

166122021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4932.

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

The square root of 166122021 is about 12888.8331900137. The cubic root of 166122021 is about 549.7210938517.

Adding to 166122021 its reverse (120221661), we get a palindrome (286343682).

The spelling of 166122021 in words is "one hundred sixty-six million, one hundred twenty-two thousand, twenty-one".