28618405 has 4 divisors (see below), whose sum is σ = 34342092. Its totient is φ = 22894720.

The previous prime is 28618379. The next prime is 28618411. The reversal of 28618405 is 50481682.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8958049 + 19660356 = 2993^2 + 4434^2 .

It is not a de Polignac number, because 28618405 - 2⁹ = 28617893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2861836 + ... + 2861845.

It is an arithmetic number, because the mean of its divisors is an integer number (8585523).

Almost surely, 2^28618405 is an apocalyptic number.

It is an amenable number.

28618405 is a deficient number, since it is larger than the sum of its proper divisors (5723687).

28618405 is an equidigital number, since it uses as much as digits as its factorization.

28618405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5723686.

The product of its (nonzero) digits is 15360, while the sum is 34.

The square root of 28618405 is about 5349.6172760301. The cubic root of 28618405 is about 305.8781642925.

The spelling of 28618405 in words is "twenty-eight million, six hundred eighteen thousand, four hundred five".