28731905 has 8 divisors (see below), whose sum is σ = 34915200. Its totient is φ = 22694256.

The previous prime is 28731893. The next prime is 28731917. The reversal of 28731905 is 50913782.

It is an interprime number because it is at equal distance from previous prime (28731893) and next prime (28731917).

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 28731905 - 2¹⁰ = 28730881 is a prime.

It is an unprimeable number.

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, 35975 + ... + 36764.

It is an arithmetic number, because the mean of its divisors is an integer number (4364400).

Almost surely, 2^28731905 is an apocalyptic number.

It is an amenable number.

28731905 is a deficient number, since it is larger than the sum of its proper divisors (6183295).

28731905 is an equidigital number, since it uses as much as digits as its factorization.

28731905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72823.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 28731905 is about 5360.2150143441. The cubic root of 28731905 is about 306.2819997106.

The spelling of 28731905 in words is "twenty-eight million, seven hundred thirty-one thousand, nine hundred five".