28782331 has 2 divisors, whose sum is σ = 28782332. Its totient is φ = 28782330.

The previous prime is 28782319. The next prime is 28782349. The reversal of 28782331 is 13328782.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28782331 - 2⁷ = 28782203 is a prime.

It is a super-2 number, since 2×28782331² = 1656845155587122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28782031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14391165 + 14391166.

It is an arithmetic number, because the mean of its divisors is an integer number (14391166).

Almost surely, 2^28782331 is an apocalyptic number.

28782331 is a deficient number, since it is larger than the sum of its proper divisors (1).

28782331 is an equidigital number, since it uses as much as digits as its factorization.

28782331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16128, while the sum is 34.

The square root of 28782331 is about 5364.9166815525. The cubic root of 28782331 is about 306.4610753127.

The spelling of 28782331 in words is "twenty-eight million, seven hundred eighty-two thousand, three hundred thirty-one".