28577520 has 120 divisors (see below), whose sum is σ = 101072400. Its totient is φ = 7216128.

The previous prime is 28577509. The next prime is 28577531. The reversal of 28577520 is 2577582.

It is an interprime number because it is at equal distance from previous prime (28577509) and next prime (28577531).

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12636 + ... + 14724.

It is an arithmetic number, because the mean of its divisors is an integer number (842270).

Almost surely, 2^28577520 is an apocalyptic number.

28577520 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 28577520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50536200).

28577520 is an abundant number, since it is smaller than the sum of its proper divisors (72494880).

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

28577520 is a wasteful number, since it uses less digits than its factorization.

28577520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2127 (or 2118 counting only the distinct ones).

The product of its (nonzero) digits is 39200, while the sum is 36.

The square root of 28577520 is about 5345.7946088491. The cubic root of 28577520 is about 305.7324330301.

The spelling of 28577520 in words is "twenty-eight million, five hundred seventy-seven thousand, five hundred twenty".