20018640928249 has 2 divisors, whose sum is σ = 20018640928250. Its totient is φ = 20018640928248.

The previous prime is 20018640928183. The next prime is 20018640928291. The reversal of 20018640928249 is 94282904681002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18082905760000 + 1935735168249 = 4252400^2 + 1391307^2 .

It is a cyclic number.

It is not a de Polignac number, because 20018640928249 - 2⁹ = 20018640927737 is a prime.

It is a super-2 number, since 2×20018640928249² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20018640928249.

It is not a weakly prime, because it can be changed into another prime (20018640328249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10009320464124 + 10009320464125.

It is an arithmetic number, because the mean of its divisors is an integer number (10009320464125).

Almost surely, 2^{20018640928249} is an apocalyptic number.

It is an amenable number.

20018640928249 is a deficient number, since it is larger than the sum of its proper divisors (1).

20018640928249 is an equidigital number, since it uses as much as digits as its factorization.

20018640928249 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3981312, while the sum is 55.

The spelling of 20018640928249 in words is "twenty trillion, eighteen billion, six hundred forty million, nine hundred twenty-eight thousand, two hundred forty-nine".