138428655 has 16 divisors (see below), whose sum is σ = 227472864. Its totient is φ = 71832960.

The previous prime is 138428621. The next prime is 138428683. The reversal of 138428655 is 556824831.

It is not a de Polignac number, because 138428655 - 2¹⁴ = 138412271 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 124156 + ... + 125265.

It is an arithmetic number, because the mean of its divisors is an integer number (14217054).

Almost surely, 2^138428655 is an apocalyptic number.

138428655 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

138428655 is a deficient number, since it is larger than the sum of its proper divisors (89044209).

138428655 is a wasteful number, since it uses less digits than its factorization.

138428655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249466.

The product of its digits is 230400, while the sum is 42.

The square root of 138428655 is about 11765.5707468869. The cubic root of 138428655 is about 517.2994298471.

The spelling of 138428655 in words is "one hundred thirty-eight million, four hundred twenty-eight thousand, six hundred fifty-five".