20510923 has 2 divisors, whose sum is σ = 20510924. Its totient is φ = 20510922.

The previous prime is 20510909. The next prime is 20510929. The reversal of 20510923 is 32901502.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20510923 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20510894 and 20510903.

It is not a weakly prime, because it can be changed into another prime (20510929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10255461 + 10255462.

It is an arithmetic number, because the mean of its divisors is an integer number (10255462).

Almost surely, 2^20510923 is an apocalyptic number.

20510923 is a deficient number, since it is larger than the sum of its proper divisors (1).

20510923 is an equidigital number, since it uses as much as digits as its factorization.

20510923 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 540, while the sum is 22.

The square root of 20510923 is about 4528.8986519903. The cubic root of 20510923 is about 273.7337842677.

The spelling of 20510923 in words is "twenty million, five hundred ten thousand, nine hundred twenty-three".