28071248421 has 4 divisors (see below), whose sum is σ = 37428331232. Its totient is φ = 18714165612.

The previous prime is 28071248411. The next prime is 28071248423. The reversal of 28071248421 is 12484217082.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 28071248421 - 2¹⁸ = 28070986277 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28071248421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28071248423) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4678541401 + ... + 4678541406.

It is an arithmetic number, because the mean of its divisors is an integer number (9357082808).

Almost surely, 2^28071248421 is an apocalyptic number.

It is an amenable number.

28071248421 is a deficient number, since it is larger than the sum of its proper divisors (9357082811).

28071248421 is an equidigital number, since it uses as much as digits as its factorization.

28071248421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9357082810.

The product of its (nonzero) digits is 57344, while the sum is 39.

The spelling of 28071248421 in words is "twenty-eight billion, seventy-one million, two hundred forty-eight thousand, four hundred twenty-one".