28801331 has 4 divisors (see below), whose sum is σ = 31016832. Its totient is φ = 26585832.

The previous prime is 28801319. The next prime is 28801351. The reversal of 28801331 is 13310882.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 28801331 - 2¹⁴ = 28784947 is a prime.

It is a super-2 number, since 2×28801331² = 1659033334743122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28801331.

It is not an unprimeable number, because it can be changed into a prime (28801351) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1107731 + ... + 1107756.

It is an arithmetic number, because the mean of its divisors is an integer number (7754208).

Almost surely, 2^28801331 is an apocalyptic number.

28801331 is a deficient number, since it is larger than the sum of its proper divisors (2215501).

28801331 is a wasteful number, since it uses less digits than its factorization.

28801331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2215500.

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 28801331 is about 5366.6871531700. The cubic root of 28801331 is about 306.5284949118.

The spelling of 28801331 in words is "twenty-eight million, eight hundred one thousand, three hundred thirty-one".