166213237 has 2 divisors, whose sum is σ = 166213238. Its totient is φ = 166213236.

The previous prime is 166213183. The next prime is 166213253. The reversal of 166213237 is 732312661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 99480676 + 66732561 = 9974^2 + 8169^2 .

It is a cyclic number.

It is not a de Polignac number, because 166213237 - 2⁷ = 166213109 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 166213199 and 166213208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166213277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83106618 + 83106619.

It is an arithmetic number, because the mean of its divisors is an integer number (83106619).

Almost surely, 2^166213237 is an apocalyptic number.

It is an amenable number.

166213237 is a deficient number, since it is larger than the sum of its proper divisors (1).

166213237 is an equidigital number, since it uses as much as digits as its factorization.

166213237 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 31.

The square root of 166213237 is about 12892.3712714147. The cubic root of 166213237 is about 549.8216909591.

Adding to 166213237 its reverse (732312661), we get a palindrome (898525898).

The spelling of 166213237 in words is "one hundred sixty-six million, two hundred thirteen thousand, two hundred thirty-seven".