20923117 has 2 divisors, whose sum is σ = 20923118. Its totient is φ = 20923116.

The previous prime is 20923103. The next prime is 20923121. The reversal of 20923117 is 71132902.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17926756 + 2996361 = 4234^2 + 1731^2 .

It is a cyclic number.

It is not a de Polignac number, because 20923117 - 2¹⁵ = 20890349 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20923091 and 20923100.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20923157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10461558 + 10461559.

It is an arithmetic number, because the mean of its divisors is an integer number (10461559).

Almost surely, 2^20923117 is an apocalyptic number.

It is an amenable number.

20923117 is a deficient number, since it is larger than the sum of its proper divisors (1).

20923117 is an equidigital number, since it uses as much as digits as its factorization.

20923117 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 20923117 is about 4574.1793799544. The cubic root of 20923117 is about 275.5553164441. Note that the first 3 decimals are identical.

The spelling of 20923117 in words is "twenty million, nine hundred twenty-three thousand, one hundred seventeen".