326666661 has 4 divisors (see below), whose sum is σ = 435555552. Its totient is φ = 217777772.

The previous prime is 326666653. The next prime is 326666671. The reversal of 326666661 is 166666623.

It is a happy number.

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 326666661 - 2³ = 326666653 is a prime.

It is a super-2 number, since 2×326666661² = 213422214817777842, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (326666671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54444441 + ... + 54444446.

It is an arithmetic number, because the mean of its divisors is an integer number (108888888).

Almost surely, 2^326666661 is an apocalyptic number.

It is an amenable number.

326666661 is a deficient number, since it is larger than the sum of its proper divisors (108888891).

326666661 is a wasteful number, since it uses less digits than its factorization.

326666661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108888890.

The product of its digits is 279936, while the sum is 42.

The square root of 326666661 is about 18073.9221255377. The cubic root of 326666661 is about 688.7076987820.

The spelling of 326666661 in words is "three hundred twenty-six million, six hundred sixty-six thousand, six hundred sixty-one".