3666121 has 2 divisors, whose sum is σ = 3666122. Its totient is φ = 3666120.

The previous prime is 3666119. The next prime is 3666127. The reversal of 3666121 is 1216663.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3553225 + 112896 = 1885^2 + 336^2 .

It is a cyclic number.

It is not a de Polignac number, because 3666121 - 2¹ = 3666119 is a prime.

Together with 3666119, it forms a pair of twin primes.

3666121 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (3666127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1833060 + 1833061.

It is an arithmetic number, because the mean of its divisors is an integer number (1833061).

Almost surely, 2^3666121 is an apocalyptic number.

It is an amenable number.

3666121 is a deficient number, since it is larger than the sum of its proper divisors (1).

3666121 is an equidigital number, since it uses as much as digits as its factorization.

3666121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1296, while the sum is 25.

The square root of 3666121 is about 1914.7117276499. The cubic root of 3666121 is about 154.1945172312.

The spelling of 3666121 in words is "three million, six hundred sixty-six thousand, one hundred twenty-one".