138645 has 32 divisors (see below), whose sum is σ = 268800.
Its totient is φ = 67392.
The previous prime is 138641. The next prime is 138647. The reversal of 138645 is 546831.
It can be divided in two parts, 1386 and 45, that added together give a triangular number (1431 = T53).
138645 = T90 + T91 + ... +
138645 is a `hidden beast` number, since 13 + 8 + 645 = 666.
138645 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 138645 - 22 = 138641 is a prime.
It is a Harshad number since it is a multiple of its sum of digits (27).
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (138641) by changing a digit.
It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1716 + ... + 1794.
It is an arithmetic number, because the mean of its divisors is an integer number (8400).
2138645 is an apocalyptic number.
138645 is a gapful number since it is divisible by the number (15) formed by its first and last digit.
It is an amenable number.
138645 is a deficient number, since it is larger than the sum of its proper divisors (130155).
138645 is a wasteful number, since it uses less digits than its factorization.
138645 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 106 (or 100 counting only the distinct ones).
The product of its digits is 2880, while the sum is 27.
The square root of 138645 is about 372.3506411972.
The cubic root of 138645 is about 51.7568778928.
The spelling of 138645 in words is "one hundred thirty-eight thousand, six hundred forty-five".