166421149 has 2 divisors, whose sum is σ = 166421150. Its totient is φ = 166421148.

The previous prime is 166421147. The next prime is 166421159. The reversal of 166421149 is 941124661.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 148401124 + 18020025 = 12182^2 + 4245^2 .

It is an emirp because it is prime and its reverse (941124661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 166421149 - 2¹ = 166421147 is a prime.

Together with 166421147, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (166421147) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83210574 + 83210575.

It is an arithmetic number, because the mean of its divisors is an integer number (83210575).

Almost surely, 2^166421149 is an apocalyptic number.

It is an amenable number.

166421149 is a deficient number, since it is larger than the sum of its proper divisors (1).

166421149 is an equidigital number, since it uses as much as digits as its factorization.

166421149 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368, while the sum is 34.

The square root of 166421149 is about 12900.4321245453. The cubic root of 166421149 is about 550.0508481914.

The spelling of 166421149 in words is "one hundred sixty-six million, four hundred twenty-one thousand, one hundred forty-nine".