138619591 has 8 divisors (see below), whose sum is σ = 154439424. Its totient is φ = 123336120.

The previous prime is 138619589. The next prime is 138619639. The reversal of 138619591 is 195916831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 138619591 - 2¹ = 138619589 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138619541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 133545 + ... + 134578.

It is an arithmetic number, because the mean of its divisors is an integer number (19304928).

Almost surely, 2^138619591 is an apocalyptic number.

138619591 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

138619591 is a deficient number, since it is larger than the sum of its proper divisors (15819833).

138619591 is a wasteful number, since it uses less digits than its factorization.

138619591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 268181.

The product of its digits is 58320, while the sum is 43.

The square root of 138619591 is about 11773.6821343197. The cubic root of 138619591 is about 517.5371593036.

The spelling of 138619591 in words is "one hundred thirty-eight million, six hundred nineteen thousand, five hundred ninety-one".