666602121 has 16 divisors (see below), whose sum is σ = 902332800. Its totient is φ = 437683200.

The previous prime is 666602117. The next prime is 666602171. The reversal of 666602121 is 121206666.

It is not a de Polignac number, because 666602121 - 2² = 666602117 is a prime.

It is not an unprimeable number, because it can be changed into a prime (666602171) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 52780 + ... + 64178.

It is an arithmetic number, because the mean of its divisors is an integer number (56395800).

Almost surely, 2^666602121 is an apocalyptic number.

It is an amenable number.

666602121 is a deficient number, since it is larger than the sum of its proper divisors (235730679).

666602121 is a wasteful number, since it uses less digits than its factorization.

666602121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11696.

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 666602121 is about 25818.6390230004. The cubic root of 666602121 is about 873.5522709096.

Adding to 666602121 its reverse (121206666), we get a palindrome (787808787).

The spelling of 666602121 in words is "six hundred sixty-six million, six hundred two thousand, one hundred twenty-one".