28897861 has 8 divisors (see below), whose sum is σ = 29350944. Its totient is φ = 28447440.

The previous prime is 28897801. The next prime is 28897873. The reversal of 28897861 is 16879882.

28897861 = 209² + 210² + ... + 457².

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28897861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28897801) 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 in 7 ways as a sum of consecutive naturals, for example, 34530 + ... + 35356.

It is an arithmetic number, because the mean of its divisors is an integer number (3668868).

Almost surely, 2^28897861 is an apocalyptic number.

It is an amenable number.

28897861 is a deficient number, since it is larger than the sum of its proper divisors (453083).

28897861 is an equidigital number, since it uses as much as digits as its factorization.

28897861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1331.

The product of its digits is 387072, while the sum is 49.

The square root of 28897861 is about 5375.6730741369. The cubic root of 28897861 is about 306.8705647530.

The spelling of 28897861 in words is "twenty-eight million, eight hundred ninety-seven thousand, eight hundred sixty-one".