28578881 has 2 divisors, whose sum is σ = 28578882. Its totient is φ = 28578880.

The previous prime is 28578863. The next prime is 28578899. The reversal of 28578881 is 18887582.

It is a balanced prime because it is at equal distance from previous prime (28578863) and next prime (28578899).

It can be written as a sum of positive squares in only one way, i.e., 23668225 + 4910656 = 4865^2 + 2216^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28578881 is a prime.

It is a super-2 number, since 2×28578881² = 1633504878424322, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28578821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14289440 + 14289441.

It is an arithmetic number, because the mean of its divisors is an integer number (14289441).

Almost surely, 2^28578881 is an apocalyptic number.

It is an amenable number.

28578881 is a deficient number, since it is larger than the sum of its proper divisors (1).

28578881 is an equidigital number, since it uses as much as digits as its factorization.

28578881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 286720, while the sum is 47.

The square root of 28578881 is about 5345.9219036570. The cubic root of 28578881 is about 305.7372864398.

The spelling of 28578881 in words is "twenty-eight million, five hundred seventy-eight thousand, eight hundred eighty-one".