28820525 has 18 divisors (see below), whose sum is σ = 37972830. Its totient is φ = 21694720.

The previous prime is 28820513. The next prime is 28820527. The reversal of 28820525 is 52502882.

It is a happy number.

It can be written as a sum of positive squares in 9 ways, for example, as 1811716 + 27008809 = 1346^2 + 5197^2 .

It is not a de Polignac number, because 28820525 - 2⁸ = 28820269 is a prime.

It is a super-2 number, since 2×28820525² = 1661245322551250, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28820491 and 28820500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28820527) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 5231 + ... + 9219.

Almost surely, 2^28820525 is an apocalyptic number.

28820525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

28820525 is a deficient number, since it is larger than the sum of its proper divisors (9152305).

28820525 is a wasteful number, since it uses less digits than its factorization.

28820525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4033 (or 4011 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 32.

The square root of 28820525 is about 5368.4751093770. The cubic root of 28820525 is about 306.5965728007.

The spelling of 28820525 in words is "twenty-eight million, eight hundred twenty thousand, five hundred twenty-five".