28912649 has 4 divisors (see below), whose sum is σ = 29096964. Its totient is φ = 28728336.

The previous prime is 28912643. The next prime is 28912669. The reversal of 28912649 is 94621982.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13191424 + 15721225 = 3632^2 + 3965^2 .

It is a cyclic number.

It is not a de Polignac number, because 28912649 - 2¹² = 28908553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28912643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 91922 + ... + 92235.

It is an arithmetic number, because the mean of its divisors is an integer number (7274241).

Almost surely, 2^28912649 is an apocalyptic number.

It is an amenable number.

28912649 is a deficient number, since it is larger than the sum of its proper divisors (184315).

28912649 is a wasteful number, since it uses less digits than its factorization.

28912649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 184314.

The product of its digits is 62208, while the sum is 41.

The square root of 28912649 is about 5377.0483538834. The cubic root of 28912649 is about 306.9229011300.

The spelling of 28912649 in words is "twenty-eight million, nine hundred twelve thousand, six hundred forty-nine".