28321971 has 8 divisors (see below), whose sum is σ = 38294784. Its totient is φ = 18615240.

The previous prime is 28321967. The next prime is 28321973. The reversal of 28321971 is 17912382.

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

It is not a de Polignac number, because 28321971 - 2² = 28321967 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28321973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 66271 + ... + 66696.

It is an arithmetic number, because the mean of its divisors is an integer number (4786848).

Almost surely, 2^28321971 is an apocalyptic number.

28321971 is a deficient number, since it is larger than the sum of its proper divisors (9972813).

28321971 is a wasteful number, since it uses less digits than its factorization.

28321971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133041.

The product of its digits is 6048, while the sum is 33.

The square root of 28321971 is about 5321.8390618282. The cubic root of 28321971 is about 304.8183851139.

It can be divided in two parts, 28321 and 971, that added together give a palindrome (29292).

The spelling of 28321971 in words is "twenty-eight million, three hundred twenty-one thousand, nine hundred seventy-one".