28403091 has 24 divisors (see below), whose sum is σ = 43819776. Its totient is φ = 17685360.

The previous prime is 28403083. The next prime is 28403113. The reversal of 28403091 is 19030482.

It is not a de Polignac number, because 28403091 - 2³ = 28403083 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28403021) 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 23 ways as a sum of consecutive naturals, for example, 7306 + ... + 10496.

It is an arithmetic number, because the mean of its divisors is an integer number (1825824).

Almost surely, 2^28403091 is an apocalyptic number.

28403091 is a deficient number, since it is larger than the sum of its proper divisors (15416685).

28403091 is a wasteful number, since it uses less digits than its factorization.

28403091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3263 (or 3260 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 28403091 is about 5329.4550378064. The cubic root of 28403091 is about 305.1091287356.

The spelling of 28403091 in words is "twenty-eight million, four hundred three thousand, ninety-one".