28555791437 has 4 divisors (see below), whose sum is σ = 28645873116. Its totient is φ = 28465709760.

The previous prime is 28555791431. The next prime is 28555791503. The reversal of 28555791437 is 73419755582.

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 9117576196 + 19438215241 = 95486^2 + 139421^2 .

It is a cyclic number.

It is not a de Polignac number, because 28555791437 - 2¹⁸ = 28555529293 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 (28555791431) by changing a digit.

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, 45040364 + ... + 45040997.

It is an arithmetic number, because the mean of its divisors is an integer number (7161468279).

Almost surely, 2^28555791437 is an apocalyptic number.

It is an amenable number.

28555791437 is a deficient number, since it is larger than the sum of its proper divisors (90081679).

28555791437 is an equidigital number, since it uses as much as digits as its factorization.

28555791437 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90081678.

The product of its digits is 10584000, while the sum is 56.

The spelling of 28555791437 in words is "twenty-eight billion, five hundred fifty-five million, seven hundred ninety-one thousand, four hundred thirty-seven".