28100520 has 288 divisors, whose sum is σ = 112039200. Its totient is φ = 6314112.

The previous prime is 28100519. The next prime is 28100521. The reversal of 28100520 is 2500182.

It is an interprime number because it is at equal distance from previous prime (28100519) and next prime (28100521).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 28100493 and 28100502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28100521) 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 71 ways as a sum of consecutive naturals, for example, 476251 + ... + 476309.

It is an arithmetic number, because the mean of its divisors is an integer number (389025).

Almost surely, 2^28100520 is an apocalyptic number.

28100520 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 28100520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56019600).

28100520 is an abundant number, since it is smaller than the sum of its proper divisors (83938680).

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

28100520 is a wasteful number, since it uses less digits than its factorization.

28100520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99 (or 76 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 28100520 is about 5300.9923599266. The cubic root of 28100520 is about 304.0218416902.

The spelling of 28100520 in words is "twenty-eight million, one hundred thousand, five hundred twenty".