28571409 has 12 divisors (see below), whose sum is σ = 42693300. Its totient is φ = 18390624.

The previous prime is 28571401. The next prime is 28571423. The reversal of 28571409 is 90417582.

It can be written as a sum of positive squares in 2 ways, for example, as 20277009 + 8294400 = 4503^2 + 2880^2 .

It is not a de Polignac number, because 28571409 - 2³ = 28571401 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28571401) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 54474 + ... + 54995.

It is an arithmetic number, because the mean of its divisors is an integer number (3557775).

Almost surely, 2^28571409 is an apocalyptic number.

28571409 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

28571409 is a deficient number, since it is larger than the sum of its proper divisors (14121891).

28571409 is a wasteful number, since it uses less digits than its factorization.

28571409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109504 (or 109501 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 28571409 is about 5345.2230075087. The cubic root of 28571409 is about 305.7106389289.

The spelling of 28571409 in words is "twenty-eight million, five hundred seventy-one thousand, four hundred nine".