28791275 has 6 divisors (see below), whose sum is σ = 35701212. Its totient is φ = 23033000.

The previous prime is 28791271. The next prime is 28791277. The reversal of 28791275 is 57219782.

It is not a de Polignac number, because 28791275 - 2² = 28791271 is a prime.

It is a super-2 number, since 2×28791275² = 1657875032251250, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28791271) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 575801 + ... + 575850.

It is an arithmetic number, because the mean of its divisors is an integer number (5950202).

Almost surely, 2^28791275 is an apocalyptic number.

28791275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

28791275 is a deficient number, since it is larger than the sum of its proper divisors (6909937).

28791275 is a wasteful number, since it uses less digits than its factorization.

28791275 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1151661 (or 1151656 counting only the distinct ones).

The product of its digits is 70560, while the sum is 41.

The square root of 28791275 is about 5365.7501805433. The cubic root of 28791275 is about 306.4928158968.

The spelling of 28791275 in words is "twenty-eight million, seven hundred ninety-one thousand, two hundred seventy-five".