138471091 has 4 divisors (see below), whose sum is σ = 151059384. Its totient is φ = 125882800.

The previous prime is 138471043. The next prime is 138471097. The reversal of 138471091 is 190174831.

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 138471091 - 2¹⁵ = 138438323 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138471097) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6294130 + ... + 6294151.

It is an arithmetic number, because the mean of its divisors is an integer number (37764846).

Almost surely, 2^138471091 is an apocalyptic number.

138471091 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

138471091 is a deficient number, since it is larger than the sum of its proper divisors (12588293).

138471091 is a wasteful number, since it uses less digits than its factorization.

138471091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12588292.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 138471091 is about 11767.3740061239. The cubic root of 138471091 is about 517.3522846933.

The spelling of 138471091 in words is "one hundred thirty-eight million, four hundred seventy-one thousand, ninety-one".