20768393 has 2 divisors, whose sum is σ = 20768394. Its totient is φ = 20768392.

The previous prime is 20768369. The next prime is 20768399. The reversal of 20768393 is 39386702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16875664 + 3892729 = 4108^2 + 1973^2 .

It is a cyclic number.

It is not a de Polignac number, because 20768393 - 2¹² = 20764297 is a prime.

It is a super-2 number, since 2×20768393² = 862652295604898, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20768399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10384196 + 10384197.

It is an arithmetic number, because the mean of its divisors is an integer number (10384197).

Almost surely, 2^20768393 is an apocalyptic number.

It is an amenable number.

20768393 is a deficient number, since it is larger than the sum of its proper divisors (1).

20768393 is an equidigital number, since it uses as much as digits as its factorization.

20768393 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 54432, while the sum is 38.

The square root of 20768393 is about 4557.2352364125. The cubic root of 20768393 is about 274.8744021499.

The spelling of 20768393 in words is "twenty million, seven hundred sixty-eight thousand, three hundred ninety-three".