28688266 has 4 divisors (see below), whose sum is σ = 43032402. Its totient is φ = 14344132.

The previous prime is 28688263. The next prime is 28688269. The reversal of 28688266 is 66288682.

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

It is an interprime number because it is at equal distance from previous prime (28688263) and next prime (28688269).

It can be written as a sum of positive squares in only one way, i.e., 18671041 + 10017225 = 4321^2 + 3165^2 .

It is not an unprimeable number, because it can be changed into a prime (28688263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7172065 + ... + 7172068.

Almost surely, 2^28688266 is an apocalyptic number.

28688266 is a deficient number, since it is larger than the sum of its proper divisors (14344136).

28688266 is a wasteful number, since it uses less digits than its factorization.

28688266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14344135.

The product of its digits is 442368, while the sum is 46.

The square root of 28688266 is about 5356.1428285661. The cubic root of 28688266 is about 306.1268572799.

The spelling of 28688266 in words is "twenty-eight million, six hundred eighty-eight thousand, two hundred sixty-six".