28009355477 has 4 divisors (see below), whose sum is σ = 28009697100. Its totient is φ = 28009013856.

The previous prime is 28009355453. The next prime is 28009355489. The reversal of 28009355477 is 77455390082.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 17442749041 + 10566606436 = 132071^2 + 102794^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28009355477 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 (28009355417) 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, 34163 + ... + 239135.

It is an arithmetic number, because the mean of its divisors is an integer number (7002424275).

It is a Poulet number, since it divides 2^28009355476-1.

Almost surely, 2^28009355477 is an apocalyptic number.

28009355477 is the 136649-th pentagonal number.

It is an amenable number.

28009355477 is a deficient number, since it is larger than the sum of its proper divisors (341623).

28009355477 is a wasteful number, since it uses less digits than its factorization.

28009355477 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341622.

The product of its (nonzero) digits is 2116800, while the sum is 50.

The spelling of 28009355477 in words is "twenty-eight billion, nine million, three hundred fifty-five thousand, four hundred seventy-seven".