138863819 has 4 divisors (see below), whose sum is σ = 138892944. Its totient is φ = 138834696.

The previous prime is 138863807. The next prime is 138863827. The reversal of 138863819 is 918368831.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138863819 is a prime.

It is a super-2 number, since 2×138863819² = 38566320454529522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138863839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5552 + ... + 17565.

It is an arithmetic number, because the mean of its divisors is an integer number (34723236).

Almost surely, 2^138863819 is an apocalyptic number.

138863819 is a deficient number, since it is larger than the sum of its proper divisors (29125).

138863819 is an equidigital number, since it uses as much as digits as its factorization.

138863819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29124.

The product of its digits is 248832, while the sum is 47.

The square root of 138863819 is about 11784.0493464683. The cubic root of 138863819 is about 517.8409232612.

The spelling of 138863819 in words is "one hundred thirty-eight million, eight hundred sixty-three thousand, eight hundred nineteen".