28172078 has 8 divisors (see below), whose sum is σ = 46099800. Its totient is φ = 12805480.

The previous prime is 28172069. The next prime is 28172147. The reversal of 28172078 is 87027182.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 640253 + ... + 640296.

It is an arithmetic number, because the mean of its divisors is an integer number (5762475).

Almost surely, 2^28172078 is an apocalyptic number.

28172078 is a deficient number, since it is larger than the sum of its proper divisors (17927722).

28172078 is a wasteful number, since it uses less digits than its factorization.

28172078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1280562.

The product of its (nonzero) digits is 12544, while the sum is 35.

The square root of 28172078 is about 5307.7375594504. The cubic root of 28172078 is about 304.2796869126.

It can be divided in two parts, 28 and 172078, that multiplied together give a palindrome (4818184).

The spelling of 28172078 in words is "twenty-eight million, one hundred seventy-two thousand, seventy-eight".