28900900 has 144 divisors (see below), whose sum is σ = 78744960. Its totient is φ = 8985600.

The previous prime is 28900889. The next prime is 28900913. The reversal of 28900900 is 900982.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 545274 + ... + 545326.

It is an arithmetic number, because the mean of its divisors is an integer number (546840).

Almost surely, 2^28900900 is an apocalyptic number.

28900900 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 28900900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39372480).

28900900 is an abundant number, since it is smaller than the sum of its proper divisors (49844060).

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

28900900 is a wasteful number, since it uses less digits than its factorization.

28900900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134 (or 127 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 28900900 is about 5375.9557289844. The cubic root of 28900900 is about 306.8813215694.

It can be divided in two parts, 28900 and 900, that multiplied together give a square (26010000 = 5100²).

The spelling of 28900900 in words is "twenty-eight million, nine hundred thousand, nine hundred".