28122506 has 4 divisors (see below), whose sum is σ = 42183762. Its totient is φ = 14061252.

The previous prime is 28122469. The next prime is 28122509. The reversal of 28122506 is 60522182.

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

It can be written as a sum of positive squares in only one way, i.e., 23435281 + 4687225 = 4841^2 + 2165^2 .

It is not an unprimeable number, because it can be changed into a prime (28122509) 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, 7030625 + ... + 7030628.

Almost surely, 2^28122506 is an apocalyptic number.

28122506 is a deficient number, since it is larger than the sum of its proper divisors (14061256).

28122506 is a wasteful number, since it uses less digits than its factorization.

28122506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14061255.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 28122506 is about 5303.0657171112. The cubic root of 28122506 is about 304.1011104689.

Adding to 28122506 its reverse (60522182), we get a palindrome (88644688).

The spelling of 28122506 in words is "twenty-eight million, one hundred twenty-two thousand, five hundred six".