138775819 has 32 divisors (see below), whose sum is σ = 177278976. Its totient is φ = 105719040.

The previous prime is 138775787. The next prime is 138775841. The reversal of 138775819 is 918577831.

It is not a de Polignac number, because 138775819 - 2⁵ = 138775787 is a prime.

It is a super-2 number, since 2×138775819² = 38517455878241522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (138775849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 303439 + ... + 303895.

It is an arithmetic number, because the mean of its divisors is an integer number (5539968).

Almost surely, 2^138775819 is an apocalyptic number.

138775819 is a deficient number, since it is larger than the sum of its proper divisors (38503157).

138775819 is a wasteful number, since it uses less digits than its factorization.

138775819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 595.

The product of its digits is 423360, while the sum is 49.

The square root of 138775819 is about 11780.3148939237. The cubic root of 138775819 is about 517.7315123984.

The spelling of 138775819 in words is "one hundred thirty-eight million, seven hundred seventy-five thousand, eight hundred nineteen".