28438857 has 10 divisors (see below), whose sum is σ = 42482858. Its totient is φ = 18959184.

The previous prime is 28438853. The next prime is 28438889. The reversal of 28438857 is 75883482.

It can be written as a sum of positive squares in only one way, i.e., 26873856 + 1565001 = 5184^2 + 1251^2 .

It is not a de Polignac number, because 28438857 - 2² = 28438853 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28438853) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 175468 + ... + 175629.

Almost surely, 2^28438857 is an apocalyptic number.

28438857 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

28438857 is a deficient number, since it is larger than the sum of its proper divisors (14044001).

28438857 is an equidigital number, since it uses as much as digits as its factorization.

28438857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351109 (or 351100 counting only the distinct ones).

The product of its digits is 430080, while the sum is 45.

The square root of 28438857 is about 5332.8094846900. The cubic root of 28438857 is about 305.2371424536.

The spelling of 28438857 in words is "twenty-eight million, four hundred thirty-eight thousand, eight hundred fifty-seven".