20840293 has 2 divisors, whose sum is σ = 20840294. Its totient is φ = 20840292.

The previous prime is 20840269. The next prime is 20840297. The reversal of 20840293 is 39204802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17447329 + 3392964 = 4177^2 + 1842^2 .

It is a cyclic number.

It is not a de Polignac number, because 20840293 - 2¹³ = 20832101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20840297) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10420146 + 10420147.

It is an arithmetic number, because the mean of its divisors is an integer number (10420147).

Almost surely, 2^20840293 is an apocalyptic number.

It is an amenable number.

20840293 is a deficient number, since it is larger than the sum of its proper divisors (1).

20840293 is an equidigital number, since it uses as much as digits as its factorization.

20840293 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 20840293 is about 4565.1169755002. The cubic root of 20840293 is about 275.1912410806.

The spelling of 20840293 in words is "twenty million, eight hundred forty thousand, two hundred ninety-three".