138270691 has 4 divisors (see below), whose sum is σ = 148906912. Its totient is φ = 127634472.

The previous prime is 138270679. The next prime is 138270697. The reversal of 138270691 is 196072831.

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 138270691 - 2⁷ = 138270563 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 138270691.

It is not an unprimeable number, because it can be changed into a prime (138270697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5318091 + ... + 5318116.

It is an arithmetic number, because the mean of its divisors is an integer number (37226728).

Almost surely, 2^138270691 is an apocalyptic number.

138270691 is a deficient number, since it is larger than the sum of its proper divisors (10636221).

138270691 is a wasteful number, since it uses less digits than its factorization.

138270691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10636220.

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 138270691 is about 11758.8558542062. The cubic root of 138270691 is about 517.1025876808.

The spelling of 138270691 in words is "one hundred thirty-eight million, two hundred seventy thousand, six hundred ninety-one".