188138986478 has 16 divisors (see below), whose sum is σ = 282676126320. Its totient is φ = 93913662336.

The previous prime is 188138986429. The next prime is 188138986487. The reversal of 188138986478 is 874689831881.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11323325 + ... + 11339927.

It is an arithmetic number, because the mean of its divisors is an integer number (17667257895).

Almost surely, 2^188138986478 is an apocalyptic number.

188138986478 is a deficient number, since it is larger than the sum of its proper divisors (94537139842).

188138986478 is a wasteful number, since it uses less digits than its factorization.

188138986478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25651.

The product of its digits is 148635648, while the sum is 71.

The spelling of 188138986478 in words is "one hundred eighty-eight billion, one hundred thirty-eight million, nine hundred eighty-six thousand, four hundred seventy-eight".