28909385 has 8 divisors (see below), whose sum is σ = 34727616. Its totient is φ = 23103280.

The previous prime is 28909381. The next prime is 28909399. The reversal of 28909385 is 58390982.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28909385 - 2² = 28909381 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28909381) 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, 3500 + ... + 8370.

It is an arithmetic number, because the mean of its divisors is an integer number (4340952).

Almost surely, 2^28909385 is an apocalyptic number.

It is an amenable number.

28909385 is a deficient number, since it is larger than the sum of its proper divisors (5818231).

28909385 is a wasteful number, since it uses less digits than its factorization.

28909385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6063.

The product of its (nonzero) digits is 155520, while the sum is 44.

The square root of 28909385 is about 5376.7448330751. The cubic root of 28909385 is about 306.9113510060.

The spelling of 28909385 in words is "twenty-eight million, nine hundred nine thousand, three hundred eighty-five".