966668821 has 4 divisors (see below), whose sum is σ = 966737952. Its totient is φ = 966599692.

The previous prime is 966668797. The next prime is 966668827. The reversal of 966668821 is 128866669.

966668821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 128866669 = 113 ⋅1140413.

It is a cyclic number.

It is not a de Polignac number, because 966668821 - 2¹⁵ = 966636053 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (966668827) 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, 5371 + ... + 44296.

It is an arithmetic number, because the mean of its divisors is an integer number (241684488).

Almost surely, 2^966668821 is an apocalyptic number.

It is an amenable number.

966668821 is a deficient number, since it is larger than the sum of its proper divisors (69131).

966668821 is a wasteful number, since it uses less digits than its factorization.

966668821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69130.

The product of its digits is 1492992, while the sum is 52.

The square root of 966668821 is about 31091.2981555933. The cubic root of 966668821 is about 988.7638283071.

It can be divided in two parts, 9666 and 68821, that added together give a palindrome (78487).

The spelling of 966668821 in words is "nine hundred sixty-six million, six hundred sixty-eight thousand, eight hundred twenty-one".