20865319 has 2 divisors, whose sum is σ = 20865320. Its totient is φ = 20865318.

The previous prime is 20865311. The next prime is 20865329. The reversal of 20865319 is 91356802.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20865319 - 2³ = 20865311 is a prime.

It is a super-2 number, since 2×20865319² = 870723073943522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20865311) 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, 10432659 + 10432660.

It is an arithmetic number, because the mean of its divisors is an integer number (10432660).

Almost surely, 2^20865319 is an apocalyptic number.

20865319 is a deficient number, since it is larger than the sum of its proper divisors (1).

20865319 is an equidigital number, since it uses as much as digits as its factorization.

20865319 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 20865319 is about 4567.8571562605. The cubic root of 20865319 is about 275.3013511946.

The spelling of 20865319 in words is "twenty million, eight hundred sixty-five thousand, three hundred nineteen".