20393861 has 2 divisors, whose sum is σ = 20393862. Its totient is φ = 20393860.

The previous prime is 20393839. The next prime is 20393917. The reversal of 20393861 is 16839302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19802500 + 591361 = 4450^2 + 769^2 .

It is a cyclic number.

It is not a de Polignac number, because 20393861 - 2⁶ = 20393797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20393161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10196930 + 10196931.

It is an arithmetic number, because the mean of its divisors is an integer number (10196931).

Almost surely, 2^20393861 is an apocalyptic number.

It is an amenable number.

20393861 is a deficient number, since it is larger than the sum of its proper divisors (1).

20393861 is an equidigital number, since it uses as much as digits as its factorization.

20393861 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 20393861 is about 4515.9562663959. The cubic root of 20393861 is about 273.2120300862.

The spelling of 20393861 in words is "twenty million, three hundred ninety-three thousand, eight hundred sixty-one".