138654779 has 4 divisors (see below), whose sum is σ = 141004920. Its totient is φ = 136304640.

The previous prime is 138654767. The next prime is 138654793. The reversal of 138654779 is 977456831.

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

It is a cyclic number.

It is not a de Polignac number, because 138654779 - 2¹² = 138650683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138654739) 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, 1174982 + ... + 1175099.

It is an arithmetic number, because the mean of its divisors is an integer number (35251230).

Almost surely, 2^138654779 is an apocalyptic number.

138654779 is a deficient number, since it is larger than the sum of its proper divisors (2350141).

138654779 is an equidigital number, since it uses as much as digits as its factorization.

138654779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2350140.

The product of its digits is 1270080, while the sum is 50.

The square root of 138654779 is about 11775.1763893370. The cubic root of 138654779 is about 517.5809471422.

It can be divided in two parts, 1386 and 54779, that added together give a palindrome (56165).

The spelling of 138654779 in words is "one hundred thirty-eight million, six hundred fifty-four thousand, seven hundred seventy-nine".