28931907 has 8 divisors (see below), whose sum is σ = 40253184. Its totient is φ = 18449288.

The previous prime is 28931869. The next prime is 28931911. The reversal of 28931907 is 70913982.

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 28931907 - 2⁷ = 28931779 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28931957) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 209583 + ... + 209720.

It is an arithmetic number, because the mean of its divisors is an integer number (5031648).

Almost surely, 2^28931907 is an apocalyptic number.

28931907 is a deficient number, since it is larger than the sum of its proper divisors (11321277).

28931907 is a wasteful number, since it uses less digits than its factorization.

28931907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 419329.

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

The square root of 28931907 is about 5378.8388152091. The cubic root of 28931907 is about 306.9910305889.

The spelling of 28931907 in words is "twenty-eight million, nine hundred thirty-one thousand, nine hundred seven".