28171042 has 4 divisors (see below), whose sum is σ = 42256566. Its totient is φ = 14085520.

The previous prime is 28171009. The next prime is 28171043. The reversal of 28171042 is 24017182.

It is a happy number.

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., 26635921 + 1535121 = 5161^2 + 1239^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28170998 and 28171016.

It is not an unprimeable number, because it can be changed into a prime (28171043) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7042759 + ... + 7042762.

Almost surely, 2^28171042 is an apocalyptic number.

28171042 is a deficient number, since it is larger than the sum of its proper divisors (14085524).

28171042 is a wasteful number, since it uses less digits than its factorization.

28171042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14085523.

The product of its (nonzero) digits is 896, while the sum is 25.

The square root of 28171042 is about 5307.6399651823. The cubic root of 28171042 is about 304.2759570064.

The spelling of 28171042 in words is "twenty-eight million, one hundred seventy-one thousand, forty-two".