20246309 has 2 divisors, whose sum is σ = 20246310. Its totient is φ = 20246308.

The previous prime is 20246299. The next prime is 20246329. The reversal of 20246309 is 90364202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17430625 + 2815684 = 4175^2 + 1678^2 .

It is a cyclic number.

It is not a de Polignac number, because 20246309 - 2⁴ = 20246293 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20246329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10123154 + 10123155.

It is an arithmetic number, because the mean of its divisors is an integer number (10123155).

Almost surely, 2^20246309 is an apocalyptic number.

It is an amenable number.

20246309 is a deficient number, since it is larger than the sum of its proper divisors (1).

20246309 is an equidigital number, since it uses as much as digits as its factorization.

20246309 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 20246309 is about 4499.5898701993. The cubic root of 20246309 is about 272.5515274442.

The spelling of 20246309 in words is "twenty million, two hundred forty-six thousand, three hundred nine".