166236220331 has 4 divisors (see below), whose sum is σ = 166366195200. Its totient is φ = 166106245464.

The previous prime is 166236220301. The next prime is 166236220343. The reversal of 166236220331 is 133022632661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 133022632661 = 4967 ⋅26781283.

It is a cyclic number.

It is not a de Polignac number, because 166236220331 - 2²⁶ = 166169111467 is a prime.

It is a super-2 number, since 2×166236220331² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 166236220291 and 166236220300.

It is not an unprimeable number, because it can be changed into a prime (166236220301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64985516 + ... + 64988073.

It is an arithmetic number, because the mean of its divisors is an integer number (41591548800).

Almost surely, 2^166236220331 is an apocalyptic number.

166236220331 is a deficient number, since it is larger than the sum of its proper divisors (129974869).

166236220331 is a wasteful number, since it uses less digits than its factorization.

166236220331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129974868.

The product of its (nonzero) digits is 46656, while the sum is 35.

Adding to 166236220331 its reverse (133022632661), we get a palindrome (299258852992).

The spelling of 166236220331 in words is "one hundred sixty-six billion, two hundred thirty-six million, two hundred twenty thousand, three hundred thirty-one".