28820916385 has 4 divisors (see below), whose sum is σ = 34585099668. Its totient is φ = 23056733104.

The previous prime is 28820916361. The next prime is 28820916401. The reversal of 28820916385 is 58361902882.

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 21237815824 + 7583100561 = 145732^2 + 87081^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28820916385 is a prime.

It is a super-2 number, since 2×28820916385² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2882091634 + ... + 2882091643.

It is an arithmetic number, because the mean of its divisors is an integer number (8646274917).

Almost surely, 2^28820916385 is an apocalyptic number.

It is an amenable number.

28820916385 is a deficient number, since it is larger than the sum of its proper divisors (5764183283).

28820916385 is an equidigital number, since it uses as much as digits as its factorization.

28820916385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5764183282.

The product of its (nonzero) digits is 1658880, while the sum is 52.

The spelling of 28820916385 in words is "twenty-eight billion, eight hundred twenty million, nine hundred sixteen thousand, three hundred eighty-five".