28057731145 has 4 divisors (see below), whose sum is σ = 33669277380. Its totient is φ = 22446184912.

The previous prime is 28057731133. The next prime is 28057731173. The reversal of 28057731145 is 54113775082.

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 7490729401 + 20567001744 = 86549^2 + 143412^2 .

It is a cyclic number.

It is not a de Polignac number, because 28057731145 - 2¹⁵ = 28057698377 is a prime.

It is a super-2 number, since 2×28057731145² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2805773110 + ... + 2805773119.

It is an arithmetic number, because the mean of its divisors is an integer number (8417319345).

Almost surely, 2^28057731145 is an apocalyptic number.

It is an amenable number.

28057731145 is a deficient number, since it is larger than the sum of its proper divisors (5611546235).

28057731145 is an equidigital number, since it uses as much as digits as its factorization.

28057731145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5611546234.

The product of its (nonzero) digits is 235200, while the sum is 43.

The spelling of 28057731145 in words is "twenty-eight billion, fifty-seven million, seven hundred thirty-one thousand, one hundred forty-five".