28172502 has 32 divisors (see below), whose sum is σ = 66290400. Its totient is φ = 8838144.

The previous prime is 28172479. The next prime is 28172513. The reversal of 28172502 is 20527182.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14427 + ... + 16262.

It is an arithmetic number, because the mean of its divisors is an integer number (2071575).

Almost surely, 2^28172502 is an apocalyptic number.

28172502 is an abundant number, since it is smaller than the sum of its proper divisors (38117898).

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

28172502 is a wasteful number, since it uses less digits than its factorization.

28172502 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30717 (or 30711 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 27.

The square root of 28172502 is about 5307.7775009885. Note that the first 3 decimals coincide. The cubic root of 28172502 is about 304.2812134115.

Adding to 28172502 its reverse (20527182), we get a palindrome (48699684).

The spelling of 28172502 in words is "twenty-eight million, one hundred seventy-two thousand, five hundred two".