20455191389 has 2 divisors, whose sum is σ = 20455191390. Its totient is φ = 20455191388.

The previous prime is 20455191343. The next prime is 20455191397. The reversal of 20455191389 is 98319155402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15434335225 + 5020856164 = 124235^2 + 70858^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20455191389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20455191319) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10227595694 + 10227595695.

It is an arithmetic number, because the mean of its divisors is an integer number (10227595695).

Almost surely, 2^20455191389 is an apocalyptic number.

It is an amenable number.

20455191389 is a deficient number, since it is larger than the sum of its proper divisors (1).

20455191389 is an equidigital number, since it uses as much as digits as its factorization.

20455191389 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 388800, while the sum is 47.

The spelling of 20455191389 in words is "twenty billion, four hundred fifty-five million, one hundred ninety-one thousand, three hundred eighty-nine".