28991200 has 144 divisors (see below), whose sum is σ = 83994624. Its totient is φ = 9561600.

The previous prime is 28991197. The next prime is 28991203. The reversal of 28991200 is 219982.

It is an interprime number because it is at equal distance from previous prime (28991197) and next prime (28991203).

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28991203) 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, 173517 + ... + 173683.

It is an arithmetic number, because the mean of its divisors is an integer number (583296).

Almost surely, 2^28991200 is an apocalyptic number.

28991200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28991200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41997312).

28991200 is an abundant number, since it is smaller than the sum of its proper divisors (55003424).

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

28991200 is a wasteful number, since it uses less digits than its factorization.

28991200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225 (or 212 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 28991200 is about 5384.3476856533. The cubic root of 28991200 is about 307.2006031166.

The spelling of 28991200 in words is "twenty-eight million, nine hundred ninety-one thousand, two hundred".