28799779409 has 2 divisors, whose sum is σ = 28799779410. Its totient is φ = 28799779408.

The previous prime is 28799779387. The next prime is 28799779451. The reversal of 28799779409 is 90497799782.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27192010000 + 1607769409 = 164900^2 + 40097^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28799779409 is a prime.

It is not a weakly prime, because it can be changed into another prime (28799779009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14399889704 + 14399889705.

It is an arithmetic number, because the mean of its divisors is an integer number (14399889705).

Almost surely, 2^28799779409 is an apocalyptic number.

It is an amenable number.

28799779409 is a deficient number, since it is larger than the sum of its proper divisors (1).

28799779409 is an equidigital number, since it uses as much as digits as its factorization.

28799779409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144027072, while the sum is 71.

The spelling of 28799779409 in words is "twenty-eight billion, seven hundred ninety-nine million, seven hundred seventy-nine thousand, four hundred nine".