138478919 has 2 divisors, whose sum is σ = 138478920. Its totient is φ = 138478918.

The previous prime is 138478913. The next prime is 138478939. The reversal of 138478919 is 919874831.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 138478919 - 2¹⁶ = 138413383 is a prime.

It is a super-2 number, since 2×138478919² = 38352822014817122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138478913) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69239459 + 69239460.

It is an arithmetic number, because the mean of its divisors is an integer number (69239460).

Almost surely, 2^138478919 is an apocalyptic number.

138478919 is a deficient number, since it is larger than the sum of its proper divisors (1).

138478919 is an equidigital number, since it uses as much as digits as its factorization.

138478919 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435456, while the sum is 50.

The square root of 138478919 is about 11767.7066159894. The cubic root of 138478919 is about 517.3620334367.

The spelling of 138478919 in words is "one hundred thirty-eight million, four hundred seventy-eight thousand, nine hundred nineteen".