20814251 has 2 divisors, whose sum is σ = 20814252. Its totient is φ = 20814250.

The previous prime is 20814203. The next prime is 20814259. The reversal of 20814251 is 15241802.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20814251 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20814259) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10407125 + 10407126.

It is an arithmetic number, because the mean of its divisors is an integer number (10407126).

Almost surely, 2^20814251 is an apocalyptic number.

20814251 is a deficient number, since it is larger than the sum of its proper divisors (1).

20814251 is an equidigital number, since it uses as much as digits as its factorization.

20814251 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 20814251 is about 4562.2638021053. The cubic root of 20814251 is about 275.0765671095.

The spelling of 20814251 in words is "twenty million, eight hundred fourteen thousand, two hundred fifty-one".