28204431394 has 32 divisors (see below), whose sum is σ = 43153190640. Its totient is φ = 13823588352.

The previous prime is 28204431391. The next prime is 28204431397. The reversal of 28204431394 is 49313440282.

It is an interprime number because it is at equal distance from previous prime (28204431391) and next prime (28204431397).

It can be written as a sum of positive squares in 8 ways, for example, as 9081137025 + 19123294369 = 95295^2 + 138287^2 .

It is not an unprimeable number, because it can be changed into a prime (28204431391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9070312 + ... + 9073420.

Almost surely, 2^28204431394 is an apocalyptic number.

28204431394 is a deficient number, since it is larger than the sum of its proper divisors (14948759246).

28204431394 is a wasteful number, since it uses less digits than its factorization.

28204431394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3654.

The product of its (nonzero) digits is 165888, while the sum is 40.

The spelling of 28204431394 in words is "twenty-eight billion, two hundred four million, four hundred thirty-one thousand, three hundred ninety-four".