138081555 has 12 divisors (see below), whose sum is σ = 239341440. Its totient is φ = 73643472.

The previous prime is 138081551. The next prime is 138081583. The reversal of 138081555 is 555180831.

138081555 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 138081555 - 2² = 138081551 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138081551) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1534195 + ... + 1534284.

It is an arithmetic number, because the mean of its divisors is an integer number (19945120).

Almost surely, 2^138081555 is an apocalyptic number.

138081555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

138081555 is a deficient number, since it is larger than the sum of its proper divisors (101259885).

138081555 is a wasteful number, since it uses less digits than its factorization.

138081555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3068490 (or 3068487 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 36.

The square root of 138081555 is about 11750.8108230879. The cubic root of 138081555 is about 516.8667041349.

The spelling of 138081555 in words is "one hundred thirty-eight million, eighty-one thousand, five hundred fifty-five".