20557326581218 has 32 divisors (see below), whose sum is σ = 37076364920448. Its totient is φ = 8363089814400.

The previous prime is 20557326581203. The next prime is 20557326581219. The reversal of 20557326581218 is 81218562375502.

It is not an unprimeable number, because it can be changed into a prime (20557326581219) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 483953868 + ... + 483996343.

It is an arithmetic number, because the mean of its divisors is an integer number (1158636403764).

Almost surely, 2^{20557326581218} is an apocalyptic number.

20557326581218 is a deficient number, since it is larger than the sum of its proper divisors (16519038339230).

20557326581218 is a wasteful number, since it uses less digits than its factorization.

20557326581218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 967950298.

The product of its (nonzero) digits is 8064000, while the sum is 55.

The spelling of 20557326581218 in words is "twenty trillion, five hundred fifty-seven billion, three hundred twenty-six million, five hundred eighty-one thousand, two hundred eighteen".