20687125 has 16 divisors (see below), whose sum is σ = 25998336. Its totient is φ = 16434000.

The previous prime is 20687087. The next prime is 20687129. The reversal of 20687125 is 52178602.

It is not a de Polignac number, because 20687125 - 2⁹ = 20686613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20687129) 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 15 ways as a sum of consecutive naturals, for example, 20380 + ... + 21370.

It is an arithmetic number, because the mean of its divisors is an integer number (1624896).

Almost surely, 2^20687125 is an apocalyptic number.

20687125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20687125 is a deficient number, since it is larger than the sum of its proper divisors (5311211).

20687125 is an equidigital number, since it uses as much as digits as its factorization.

20687125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1173 (or 1163 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 20687125 is about 4548.3101257500. The cubic root of 20687125 is about 274.5153999918.

The spelling of 20687125 in words is "twenty million, six hundred eighty-seven thousand, one hundred twenty-five".