28171899 has 12 divisors (see below), whose sum is σ = 46506096. Its totient is φ = 16098192.

The previous prime is 28171883. The next prime is 28171903. The reversal of 28171899 is 99817182.

It is not a de Polignac number, because 28171899 - 2⁴ = 28171883 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28171859) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 223524 + ... + 223649.

It is an arithmetic number, because the mean of its divisors is an integer number (3875508).

Almost surely, 2^28171899 is an apocalyptic number.

28171899 is a deficient number, since it is larger than the sum of its proper divisors (18334197).

28171899 is a wasteful number, since it uses less digits than its factorization.

28171899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 447186 (or 447183 counting only the distinct ones).

The product of its digits is 72576, while the sum is 45.

The square root of 28171899 is about 5307.7206972485. The cubic root of 28171899 is about 304.2790424662.

The spelling of 28171899 in words is "twenty-eight million, one hundred seventy-one thousand, eight hundred ninety-nine".