138578826 has 16 divisors (see below), whose sum is σ = 277956000. Its totient is φ = 46059888.

The previous prime is 138578821. The next prime is 138578827. The reversal of 138578826 is 628875831.

138578826 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (138578821) 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, 30996 + ... + 35183.

It is an arithmetic number, because the mean of its divisors is an integer number (17372250).

Almost surely, 2^138578826 is an apocalyptic number.

138578826 is an abundant number, since it is smaller than the sum of its proper divisors (139377174).

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

138578826 is a wasteful number, since it uses less digits than its factorization.

138578826 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66533.

The product of its digits is 645120, while the sum is 48.

The square root of 138578826 is about 11771.9508153916. The cubic root of 138578826 is about 517.4864221974.

The spelling of 138578826 in words is "one hundred thirty-eight million, five hundred seventy-eight thousand, eight hundred twenty-six".