28969878 has 48 divisors (see below), whose sum is σ = 67863744. Its totient is φ = 8220240.

The previous prime is 28969877. The next prime is 28969891. The reversal of 28969878 is 87896982.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28969873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 61801 + ... + 62267.

It is an arithmetic number, because the mean of its divisors is an integer number (1413828).

Almost surely, 2^28969878 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28969878, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33931872).

28969878 is an abundant number, since it is smaller than the sum of its proper divisors (38893866).

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

28969878 is a wasteful number, since it uses less digits than its factorization.

28969878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 697 (or 690 counting only the distinct ones).

The product of its digits is 3483648, while the sum is 57.

The square root of 28969878 is about 5382.3673230280. The cubic root of 28969878 is about 307.1252729277.

Subtracting from 28969878 its product of digits (3483648), we obtain a triangular number (25486230 = T₇₁₃₉).

The spelling of 28969878 in words is "twenty-eight million, nine hundred sixty-nine thousand, eight hundred seventy-eight".