18778544974440 has 128 divisors (see below), whose sum is σ = 62596431388800. Its totient is φ = 5007509475840.

The previous prime is 18778544974391. The next prime is 18778544974447. The reversal of 18778544974440 is 4447944587781.

18778544974440 is a `hidden beast` number, since 1 + 8 + 7 + 7 + 8 + 54 + 497 + 44 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (18778544974447) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 62967519 + ... + 63265041.

It is an arithmetic number, because the mean of its divisors is an integer number (489034620225).

Almost surely, 2^{18778544974440} is an apocalyptic number.

18778544974440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18778544974440 is an abundant number, since it is smaller than the sum of its proper divisors (43817886414360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18778544974440 is a wasteful number, since it uses less digits than its factorization.

18778544974440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 355984 (or 355974 counting only the distinct ones).

The product of its (nonzero) digits is 1011548160, while the sum is 72.

The spelling of 18778544974440 in words is "eighteen trillion, seven hundred seventy-eight billion, five hundred forty-four million, nine hundred seventy-four thousand, four hundred forty".