28997507 has 16 divisors (see below), whose sum is σ = 36288000. Its totient is φ = 22511040.

The previous prime is 28997491. The next prime is 28997531. The reversal of 28997507 is 70579982.

It is a cyclic number.

It is not a de Polignac number, because 28997507 - 2⁴ = 28997491 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28997707) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 27119 + ... + 28167.

It is an arithmetic number, because the mean of its divisors is an integer number (2268000).

Almost surely, 2^28997507 is an apocalyptic number.

28997507 is a deficient number, since it is larger than the sum of its proper divisors (7290493).

28997507 is a wasteful number, since it uses less digits than its factorization.

28997507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1426.

The product of its (nonzero) digits is 317520, while the sum is 47.

The square root of 28997507 is about 5384.9333329207. The cubic root of 28997507 is about 307.2228785395. Note that the first 3 decimals are identical.

The spelling of 28997507 in words is "twenty-eight million, nine hundred ninety-seven thousand, five hundred seven".