20666125 has 16 divisors (see below), whose sum is σ = 26685360. Its totient is φ = 15960000.

The previous prime is 20666111. The next prime is 20666143. The reversal of 20666125 is 52166602.

It can be written as a sum of positive squares in 8 ways, for example, as 3143529 + 17522596 = 1773^2 + 4186^2 .

It is not a de Polignac number, because 20666125 - 2²¹ = 18568973 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20666093 and 20666102.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 775 + ... + 6475.

It is an arithmetic number, because the mean of its divisors is an integer number (1667835).

Almost surely, 2^20666125 is an apocalyptic number.

20666125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20666125 is a deficient number, since it is larger than the sum of its proper divisors (6019235).

20666125 is an equidigital number, since it uses as much as digits as its factorization.

20666125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5745 (or 5735 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 20666125 is about 4546.0009898811. Note that the first 3 decimals coincide. The cubic root of 20666125 is about 274.4224794729.

It can be divided in two parts, 20 and 666125, that multiplied together give a square (13322500 = 3650²).

The spelling of 20666125 in words is "twenty million, six hundred sixty-six thousand, one hundred twenty-five".