138706429 has 2 divisors, whose sum is σ = 138706430. Its totient is φ = 138706428.

The previous prime is 138706423. The next prime is 138706439. The reversal of 138706429 is 924607831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 136843204 + 1863225 = 11698^2 + 1365^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-138706429 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 138706391 and 138706400.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138706423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69353214 + 69353215.

It is an arithmetic number, because the mean of its divisors is an integer number (69353215).

Almost surely, 2^138706429 is an apocalyptic number.

It is an amenable number.

138706429 is a deficient number, since it is larger than the sum of its proper divisors (1).

138706429 is an equidigital number, since it uses as much as digits as its factorization.

138706429 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 138706429 is about 11777.3693582226. The cubic root of 138706429 is about 517.6452068270.

The spelling of 138706429 in words is "one hundred thirty-eight million, seven hundred six thousand, four hundred twenty-nine".