28981571 has 2 divisors, whose sum is σ = 28981572. Its totient is φ = 28981570.

The previous prime is 28981531. The next prime is 28981573. The reversal of 28981571 is 17518982.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28981571 is a prime.

Together with 28981573, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_1798583 and since 28981571 and 1798583 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (28981573) 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 as a sum of consecutive naturals, namely, 14490785 + 14490786.

It is an arithmetic number, because the mean of its divisors is an integer number (14490786).

Almost surely, 2^28981571 is an apocalyptic number.

28981571 is a deficient number, since it is larger than the sum of its proper divisors (1).

28981571 is an equidigital number, since it uses as much as digits as its factorization.

28981571 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40320, while the sum is 41.

The square root of 28981571 is about 5383.4534455125. The cubic root of 28981571 is about 307.1665886322.

The spelling of 28981571 in words is "twenty-eight million, nine hundred eighty-one thousand, five hundred seventy-one".