28378342225 has 24 divisors (see below), whose sum is σ = 36999384120. Its totient is φ = 21560448000.

The previous prime is 28378342193. The next prime is 28378342247. The reversal of 28378342225 is 52224387382.

It can be written as a sum of positive squares in 12 ways, for example, as 6120089361 + 22258252864 = 78231^2 + 149192^2 .

It is not a de Polignac number, because 28378342225 - 2⁵ = 28378342193 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 276616 + ... + 365065.

It is an arithmetic number, because the mean of its divisors is an integer number (1541641005).

Almost surely, 2^28378342225 is an apocalyptic number.

28378342225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28378342225 is a deficient number, since it is larger than the sum of its proper divisors (8621041895).

28378342225 is a wasteful number, since it uses less digits than its factorization.

28378342225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 641781 (or 641776 counting only the distinct ones).

The product of its digits is 1290240, while the sum is 46.

The spelling of 28378342225 in words is "twenty-eight billion, three hundred seventy-eight million, three hundred forty-two thousand, two hundred twenty-five".