138064721478 has 16 divisors (see below), whose sum is σ = 276139892016. Its totient is φ = 46019832320.

The previous prime is 138064721477. The next prime is 138064721479. The reversal of 138064721478 is 874127460831.

138064721478 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (138064721477) and next prime (138064721479).

It is a self number, because there is not a number n which added to its sum of digits gives 138064721478.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138064721477) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 258051 + ... + 585422.

It is an arithmetic number, because the mean of its divisors is an integer number (17258743251).

Almost surely, 2^138064721478 is an apocalyptic number.

138064721478 is an abundant number, since it is smaller than the sum of its proper divisors (138075170538).

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

138064721478 is a wasteful number, since it uses less digits than its factorization.

138064721478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 870759.

The product of its (nonzero) digits is 1806336, while the sum is 51.

The spelling of 138064721478 in words is "one hundred thirty-eight billion, sixty-four million, seven hundred twenty-one thousand, four hundred seventy-eight".