20718337 has 2 divisors, whose sum is σ = 20718338. Its totient is φ = 20718336.

The previous prime is 20718311. The next prime is 20718353. The reversal of 20718337 is 73381702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16573041 + 4145296 = 4071^2 + 2036^2 .

It is a cyclic number.

It is not a de Polignac number, because 20718337 - 2¹⁵ = 20685569 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20718299 and 20718308.

It is not a weakly prime, because it can be changed into another prime (20718637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10359168 + 10359169.

It is an arithmetic number, because the mean of its divisors is an integer number (10359169).

Almost surely, 2^20718337 is an apocalyptic number.

It is an amenable number.

20718337 is a deficient number, since it is larger than the sum of its proper divisors (1).

20718337 is an equidigital number, since it uses as much as digits as its factorization.

20718337 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 20718337 is about 4551.7399969682. The cubic root of 20718337 is about 274.6533903143.

The spelling of 20718337 in words is "twenty million, seven hundred eighteen thousand, three hundred thirty-seven".