28797071809 has 9 divisors (see below), whose sum is σ = 31655031681. Its totient is φ = 26177459220.

The previous prime is 28797071803. The next prime is 28797071909. The reversal of 28797071809 is 90817079782.

The square root of 28797071809 is 169697.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 28797071809 - 2²¹ = 28794974657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28797071803) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 1858954 + ... + 1874380.

Almost surely, 2^28797071809 is an apocalyptic number.

28797071809 is the 169697-th square number.

28797071809 is the 84849-th centered octagonal number.

It is an amenable number.

28797071809 is a deficient number, since it is larger than the sum of its proper divisors (2857959872).

28797071809 is an frugal number, since it uses more digits than its factorization.

28797071809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30876 (or 15438 counting only the distinct ones).

The product of its (nonzero) digits is 3556224, while the sum is 58.

The spelling of 28797071809 in words is "twenty-eight billion, seven hundred ninety-seven million, seventy-one thousand, eight hundred nine".