20253209 has 2 divisors, whose sum is σ = 20253210. Its totient is φ = 20253208.

The previous prime is 20253197. The next prime is 20253241. The reversal of 20253209 is 90235202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15960025 + 4293184 = 3995^2 + 2072^2 .

It is a cyclic number.

It is not a de Polignac number, because 20253209 - 2¹² = 20249113 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20253109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10126604 + 10126605.

It is an arithmetic number, because the mean of its divisors is an integer number (10126605).

Almost surely, 2^20253209 is an apocalyptic number.

It is an amenable number.

20253209 is a deficient number, since it is larger than the sum of its proper divisors (1).

20253209 is an equidigital number, since it uses as much as digits as its factorization.

20253209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 20253209 is about 4500.3565414309. The cubic root of 20253209 is about 272.5824860408.

The spelling of 20253209 in words is "twenty million, two hundred fifty-three thousand, two hundred nine".