28349172 has 18 divisors (see below), whose sum is σ = 71660498. Its totient is φ = 9449712.

The previous prime is 28349171. The next prime is 28349203. The reversal of 28349172 is 27194382.

It can be written as a sum of positive squares in only one way, i.e., 19131876 + 9217296 = 4374^2 + 3036^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 787477 = 28349172 / (2 + 8 + 3 + 4 + 9 + 1 + 7 + 2).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28349171) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 393703 + ... + 393774.

Almost surely, 2^28349172 is an apocalyptic number.

It is an amenable number.

28349172 is an abundant number, since it is smaller than the sum of its proper divisors (43311326).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28349172 is a wasteful number, since it uses less digits than its factorization.

28349172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 787487 (or 787482 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 28349172 is about 5324.3940500305. The cubic root of 28349172 is about 304.9159384929.

It can be divided in two parts, 283 and 49172, that added together give a triangular number (49455 = T₃₁₄).

The spelling of 28349172 in words is "twenty-eight million, three hundred forty-nine thousand, one hundred seventy-two".