3666440121 has 4 divisors (see below), whose sum is σ = 4888586832. Its totient is φ = 2444293412.

The previous prime is 3666440117. The next prime is 3666440147. The reversal of 3666440121 is 1210446663.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 3666440121 - 2² = 3666440117 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3666440171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 611073351 + ... + 611073356.

It is an arithmetic number, because the mean of its divisors is an integer number (1222146708).

Almost surely, 2^3666440121 is an apocalyptic number.

It is an amenable number.

3666440121 is a deficient number, since it is larger than the sum of its proper divisors (1222146711).

3666440121 is a wasteful number, since it uses less digits than its factorization.

3666440121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1222146710.

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 3666440121 is about 60551.1364137784. The cubic root of 3666440121 is about 1541.9899110438.

Adding to 3666440121 its reverse (1210446663), we get a palindrome (4876886784).

The spelling of 3666440121 in words is "three billion, six hundred sixty-six million, four hundred forty thousand, one hundred twenty-one".