18878436278401 has 16 divisors (see below), whose sum is σ = 21929259651840. Its totient is φ = 15916093951680.

The previous prime is 18878436278399. The next prime is 18878436278431. The reversal of 18878436278401 is 10487263487881.

It is a cyclic number.

It is not a de Polignac number, because 18878436278401 - 2¹ = 18878436278399 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18878436278431) 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 in 15 ways as a sum of consecutive naturals, for example, 81439980 + ... + 81671458.

It is an arithmetic number, because the mean of its divisors is an integer number (1370578728240).

Almost surely, 2^{18878436278401} is an apocalyptic number.

It is an amenable number.

18878436278401 is a deficient number, since it is larger than the sum of its proper divisors (3050823373439).

18878436278401 is a wasteful number, since it uses less digits than its factorization.

18878436278401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 422544.

The product of its (nonzero) digits is 115605504, while the sum is 67.

The spelling of 18878436278401 in words is "eighteen trillion, eight hundred seventy-eight billion, four hundred thirty-six million, two hundred seventy-eight thousand, four hundred one".