28000705409 has 4 divisors (see below), whose sum is σ = 28019588016. Its totient is φ = 27981822804.

The previous prime is 28000705387. The next prime is 28000705429. The reversal of 28000705409 is 90450700082.

It is a happy number.

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 28000705409 - 2²⁸ = 27732269953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28000705429) 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, 9439079 + ... + 9442044.

It is an arithmetic number, because the mean of its divisors is an integer number (7004897004).

Almost surely, 2^28000705409 is an apocalyptic number.

It is an amenable number.

28000705409 is a deficient number, since it is larger than the sum of its proper divisors (18882607).

28000705409 is a wasteful number, since it uses less digits than its factorization.

28000705409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18882606.

The product of its (nonzero) digits is 20160, while the sum is 35.

The spelling of 28000705409 in words is "twenty-eight billion, seven hundred five thousand, four hundred nine".