28918331 has 8 divisors (see below), whose sum is σ = 31654224. Its totient is φ = 26255520.

The previous prime is 28918277. The next prime is 28918333. The reversal of 28918331 is 13381982.

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

It is a cyclic number.

It is not a de Polignac number, because 28918331 - 2¹⁰ = 28917307 is a prime.

It is a super-2 number, since 2×28918331² = 1672539735651122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28918291 and 28918300.

It is not an unprimeable number, because it can be changed into a prime (28918333) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17441 + ... + 19026.

It is an arithmetic number, because the mean of its divisors is an integer number (3956778).

Almost surely, 2^28918331 is an apocalyptic number.

28918331 is a deficient number, since it is larger than the sum of its proper divisors (2735893).

28918331 is a wasteful number, since it uses less digits than its factorization.

28918331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36541.

The product of its digits is 10368, while the sum is 35.

The square root of 28918331 is about 5377.5766847159. The cubic root of 28918331 is about 306.9430056144.

The spelling of 28918331 in words is "twenty-eight million, nine hundred eighteen thousand, three hundred thirty-one".