20565625 has 12 divisors (see below), whose sum is σ = 25709292. Its totient is φ = 16450000.

The previous prime is 20565613. The next prime is 20565637. The reversal of 20565625 is 52656502.

It is an interprime number because it is at equal distance from previous prime (20565613) and next prime (20565637).

It can be written as a sum of positive squares in 6 ways, for example, as 18844281 + 1721344 = 4341^2 + 1312^2 .

It is not a de Polignac number, because 20565625 - 2¹¹ = 20563577 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 166 + ... + 6415.

It is an arithmetic number, because the mean of its divisors is an integer number (2142441).

Almost surely, 2^20565625 is an apocalyptic number.

20565625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20565625 is a deficient number, since it is larger than the sum of its proper divisors (5143667).

20565625 is an frugal number, since it uses more digits than its factorization.

20565625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6606 (or 6586 counting only the distinct ones).

The product of its (nonzero) digits is 18000, while the sum is 31.

The square root of 20565625 is about 4534.9338473676. The cubic root of 20565625 is about 273.9769147795.

The spelling of 20565625 in words is "twenty million, five hundred sixty-five thousand, six hundred twenty-five".