28356548391 has 8 divisors (see below), whose sum is σ = 42009701360. Its totient is φ = 18904365576.

The previous prime is 28356548387. The next prime is 28356548393. The reversal of 28356548391 is 19384565382.

28356548391 is a `hidden beast` number, since 2 + 8 + 3 + 5 + 6 + 548 + 3 + 91 = 666.

It is not a de Polignac number, because 28356548391 - 2² = 28356548387 is a prime.

It is a super-2 number, since 2×28356548391² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28356548393) 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 7 ways as a sum of consecutive naturals, for example, 525121240 + ... + 525121293.

It is an arithmetic number, because the mean of its divisors is an integer number (5251212670).

Almost surely, 2^28356548391 is an apocalyptic number.

28356548391 is a deficient number, since it is larger than the sum of its proper divisors (13653152969).

28356548391 is a wasteful number, since it uses less digits than its factorization.

28356548391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1050242542 (or 1050242536 counting only the distinct ones).

The product of its digits is 6220800, while the sum is 54.

The spelling of 28356548391 in words is "twenty-eight billion, three hundred fifty-six million, five hundred forty-eight thousand, three hundred ninety-one".