28671557 has 2 divisors, whose sum is σ = 28671558. Its totient is φ = 28671556.

The previous prime is 28671527. The next prime is 28671611. The reversal of 28671557 is 75517682.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28665316 + 6241 = 5354^2 + 79^2 .

It is a cyclic number.

It is not a de Polignac number, because 28671557 - 2⁶ = 28671493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28671527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14335778 + 14335779.

It is an arithmetic number, because the mean of its divisors is an integer number (14335779).

Almost surely, 2^28671557 is an apocalyptic number.

It is an amenable number.

28671557 is a deficient number, since it is larger than the sum of its proper divisors (1).

28671557 is an equidigital number, since it uses as much as digits as its factorization.

28671557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 117600, while the sum is 41.

The square root of 28671557 is about 5354.5828035431. The cubic root of 28671557 is about 306.0674129175.

The spelling of 28671557 in words is "twenty-eight million, six hundred seventy-one thousand, five hundred fifty-seven".