28310997 has 16 divisors (see below), whose sum is σ = 44347968. Its totient is φ = 15838080.

The previous prime is 28310983. The next prime is 28311011. The reversal of 28310997 is 79901382.

It is an interprime number because it is at equal distance from previous prime (28310983) and next prime (28311011).

It is not a de Polignac number, because 28310997 - 2¹⁶ = 28245461 is a prime.

It is a super-2 number, since 2×28310997² = 1603025102268018, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28310197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32568 + ... + 33425.

It is an arithmetic number, because the mean of its divisors is an integer number (2771748).

Almost surely, 2^28310997 is an apocalyptic number.

It is an amenable number.

28310997 is a deficient number, since it is larger than the sum of its proper divisors (16036971).

28310997 is a wasteful number, since it uses less digits than its factorization.

28310997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66020.

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 28310997 is about 5320.8079273734. The cubic root of 28310997 is about 304.7790103932.

The spelling of 28310997 in words is "twenty-eight million, three hundred ten thousand, nine hundred ninety-seven".