28779407 has 4 divisors (see below), whose sum is σ = 28790736. Its totient is φ = 28768080.

The previous prime is 28779391. The next prime is 28779431. The reversal of 28779407 is 70497782.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 28779407 - 2⁴ = 28779391 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28779467) 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, 107 + ... + 7587.

It is an arithmetic number, because the mean of its divisors is an integer number (7197684).

Almost surely, 2^28779407 is an apocalyptic number.

28779407 is a deficient number, since it is larger than the sum of its proper divisors (11329).

28779407 is an equidigital number, since it uses as much as digits as its factorization.

28779407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11328.

The product of its (nonzero) digits is 197568, while the sum is 44.

The square root of 28779407 is about 5364.6441634092. The cubic root of 28779407 is about 306.4506971571.

The spelling of 28779407 in words is "twenty-eight million, seven hundred seventy-nine thousand, four hundred seven".