138455999 has 8 divisors (see below), whose sum is σ = 152510592. Its totient is φ = 124646040.

The previous prime is 138455987. The next prime is 138456011. The reversal of 138455999 is 999554831.

It is a happy number.

138455999 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (138455987) and next prime (138456011).

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 138455999 - 2¹² = 138451903 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 138455999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138455959) 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, 59969 + ... + 62234.

It is an arithmetic number, because the mean of its divisors is an integer number (19063824).

Almost surely, 2^138455999 is an apocalyptic number.

138455999 is a deficient number, since it is larger than the sum of its proper divisors (14054593).

138455999 is a wasteful number, since it uses less digits than its factorization.

138455999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122317.

The product of its digits is 1749600, while the sum is 53.

The square root of 138455999 is about 11766.7327240828. The cubic root of 138455999 is about 517.3334885574. Note that the first 3 decimals are identical.

The spelling of 138455999 in words is "one hundred thirty-eight million, four hundred fifty-five thousand, nine hundred ninety-nine".