138458409 has 8 divisors (see below), whose sum is σ = 188904672. Its totient is φ = 90158880.

The previous prime is 138458407. The next prime is 138458417. The reversal of 138458409 is 904854831.

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

It is not a de Polignac number, because 138458409 - 2¹ = 138458407 is a prime.

It is a super-2 number, since 2×138458409² = 38341462045622562, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (138458401) 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, 536532 + ... + 536789.

It is an arithmetic number, because the mean of its divisors is an integer number (23613084).

Almost surely, 2^138458409 is an apocalyptic number.

It is an amenable number.

138458409 is a deficient number, since it is larger than the sum of its proper divisors (50446263).

138458409 is a wasteful number, since it uses less digits than its factorization.

138458409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1073367.

The product of its (nonzero) digits is 138240, while the sum is 42.

The square root of 138458409 is about 11766.8351309942. The cubic root of 138458409 is about 517.3364901523.

The spelling of 138458409 in words is "one hundred thirty-eight million, four hundred fifty-eight thousand, four hundred nine".