28205397449 has 4 divisors (see below), whose sum is σ = 28602656640. Its totient is φ = 27808138260.

The previous prime is 28205397439. The next prime is 28205397497. The reversal of 28205397449 is 94479350282.

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 a cyclic number.

It is not a de Polignac number, because 28205397449 - 2²⁰ = 28204348873 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 28205397449.

It is not an unprimeable number, because it can be changed into a prime (28205397439) 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, 198629489 + ... + 198629630.

It is an arithmetic number, because the mean of its divisors is an integer number (7150664160).

Almost surely, 2^28205397449 is an apocalyptic number.

It is an amenable number.

28205397449 is a deficient number, since it is larger than the sum of its proper divisors (397259191).

28205397449 is an equidigital number, since it uses as much as digits as its factorization.

28205397449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397259190.

The product of its (nonzero) digits is 4354560, while the sum is 53.

The spelling of 28205397449 in words is "twenty-eight billion, two hundred five million, three hundred ninety-seven thousand, four hundred forty-nine".