138430639 has 2 divisors, whose sum is σ = 138430640. Its totient is φ = 138430638.

The previous prime is 138430603. The next prime is 138430681. The reversal of 138430639 is 936034831.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 138430639 - 2²⁵ = 104876207 is a prime.

It is equal to p_7828408 and since 138430639 and 7828408 have the same sum of digits, it is a Honaker prime.

It is a plaindrome in base 14.

It is a junction number, because it is equal to n+sod(n) for n = 138430598 and 138430607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138410639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69215319 + 69215320.

It is an arithmetic number, because the mean of its divisors is an integer number (69215320).

Almost surely, 2^138430639 is an apocalyptic number.

138430639 is a deficient number, since it is larger than the sum of its proper divisors (1).

138430639 is an equidigital number, since it uses as much as digits as its factorization.

138430639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 37.

The square root of 138430639 is about 11765.6550603866. The cubic root of 138430639 is about 517.3019011976.

It can be divided in two parts, 1384 and 30639, that added together give a palindrome (32023).

The spelling of 138430639 in words is "one hundred thirty-eight million, four hundred thirty thousand, six hundred thirty-nine".