28129487 has 2 divisors, whose sum is σ = 28129488. Its totient is φ = 28129486.

The previous prime is 28129477. The next prime is 28129501. The reversal of 28129487 is 78492182.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28129487 - 2⁴ = 28129471 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28129417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14064743 + 14064744.

It is an arithmetic number, because the mean of its divisors is an integer number (14064744).

Almost surely, 2^28129487 is an apocalyptic number.

28129487 is a deficient number, since it is larger than the sum of its proper divisors (1).

28129487 is an equidigital number, since it uses as much as digits as its factorization.

28129487 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64512, while the sum is 41.

The square root of 28129487 is about 5303.7238804448. The cubic root of 28129487 is about 304.1262712686.

The spelling of 28129487 in words is "twenty-eight million, one hundred twenty-nine thousand, four hundred eighty-seven".