28499972 has 6 divisors (see below), whose sum is σ = 49874958. Its totient is φ = 14249984.

The previous prime is 28499971. The next prime is 28500023. The reversal of 28499972 is 27999482.

It can be written as a sum of positive squares in only one way, i.e., 20286016 + 8213956 = 4504^2 + 2866^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 28499972.

It is not an unprimeable number, because it can be changed into a prime (28499971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3562493 + ... + 3562500.

It is an arithmetic number, because the mean of its divisors is an integer number (8312493).

Almost surely, 2^28499972 is an apocalyptic number.

It is an amenable number.

28499972 is a deficient number, since it is larger than the sum of its proper divisors (21374986).

28499972 is a wasteful number, since it uses less digits than its factorization.

28499972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7124997 (or 7124995 counting only the distinct ones).

The product of its digits is 653184, while the sum is 50.

The square root of 28499972 is about 5338.5365035747. The cubic root of 28499972 is about 305.4556371822.

It can be divided in two parts, 2849 and 9972, that added together give a palindrome (12821).

The spelling of 28499972 in words is "twenty-eight million, four hundred ninety-nine thousand, nine hundred seventy-two".