28907838 has 48 divisors (see below), whose sum is σ = 65707200. Its totient is φ = 9172800.

The previous prime is 28907831. The next prime is 28907861. The reversal of 28907838 is 83870982.

It is a junction number, because it is equal to n+sod(n) for n = 28907793 and 28907802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28907831) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40888 + ... + 41588.

It is an arithmetic number, because the mean of its divisors is an integer number (1368900).

Almost surely, 2^28907838 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28907838, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32853600).

28907838 is an abundant number, since it is smaller than the sum of its proper divisors (36799362).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28907838 is a wasteful number, since it uses less digits than its factorization.

28907838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 817 (or 814 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 28907838 is about 5376.6009708737. The cubic root of 28907838 is about 306.9058764247.

The spelling of 28907838 in words is "twenty-eight million, nine hundred seven thousand, eight hundred thirty-eight".