138729086 has 4 divisors (see below), whose sum is σ = 208093632. Its totient is φ = 69364542.

The previous prime is 138729053. The next prime is 138729091. The reversal of 138729086 is 680927831.

138729086 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 680927831 = 21277 ⋅32003.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34682270 + ... + 34682273.

It is an arithmetic number, because the mean of its divisors is an integer number (52023408).

Almost surely, 2^138729086 is an apocalyptic number.

138729086 is a deficient number, since it is larger than the sum of its proper divisors (69364546).

138729086 is an equidigital number, since it uses as much as digits as its factorization.

138729086 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69364545.

The product of its (nonzero) digits is 145152, while the sum is 44.

The square root of 138729086 is about 11778.3312060750. The cubic root of 138729086 is about 517.6733902092.

The spelling of 138729086 in words is "one hundred thirty-eight million, seven hundred twenty-nine thousand, eighty-six".