28320031 has 2 divisors, whose sum is σ = 28320032. Its totient is φ = 28320030.

The previous prime is 28320007. The next prime is 28320041. The reversal of 28320031 is 13002382.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28320031 - 2¹⁷ = 28188959 is a prime.

It is a super-2 number, since 2×28320031² = 1604048311681922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28319990 and 28320008.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28320001) 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 as a sum of consecutive naturals, namely, 14160015 + 14160016.

It is an arithmetic number, because the mean of its divisors is an integer number (14160016).

Almost surely, 2^28320031 is an apocalyptic number.

28320031 is a deficient number, since it is larger than the sum of its proper divisors (1).

28320031 is an equidigital number, since it uses as much as digits as its factorization.

28320031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 28320031 is about 5321.6567908876. The cubic root of 28320031 is about 304.8114251325.

The spelling of 28320031 in words is "twenty-eight million, three hundred twenty thousand, thirty-one".