28304836661 has 4 divisors (see below), whose sum is σ = 28305787692. Its totient is φ = 28303885632.

The previous prime is 28304836627. The next prime is 28304836673. The reversal of 28304836661 is 16663840382.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13387878436 + 14916958225 = 115706^2 + 122135^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28304836661 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 (28304866661) 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, 429380 + ... + 490893.

It is an arithmetic number, because the mean of its divisors is an integer number (7076446923).

Almost surely, 2^28304836661 is an apocalyptic number.

It is an amenable number.

28304836661 is a deficient number, since it is larger than the sum of its proper divisors (951031).

28304836661 is an equidigital number, since it uses as much as digits as its factorization.

28304836661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 951030.

The product of its (nonzero) digits is 995328, while the sum is 47.

The spelling of 28304836661 in words is "twenty-eight billion, three hundred four million, eight hundred thirty-six thousand, six hundred sixty-one".