138285405 has 18 divisors (see below), whose sum is σ = 239831514. Its totient is φ = 73710144.

The previous prime is 138285397. The next prime is 138285419. The reversal of 138285405 is 504582831.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 11655396 + 126630009 = 3414^2 + 11253^2 .

It is not a de Polignac number, because 138285405 - 2³ = 138285397 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 138285405.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 78009 + ... + 79761.

It is an arithmetic number, because the mean of its divisors is an integer number (13323973).

Almost surely, 2^138285405 is an apocalyptic number.

138285405 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

138285405 is a deficient number, since it is larger than the sum of its proper divisors (101546109).

138285405 is an frugal number, since it uses more digits than its factorization.

138285405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3517 (or 1761 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 36.

The square root of 138285405 is about 11759.4814936714. The cubic root of 138285405 is about 517.1209294266.

The spelling of 138285405 in words is "one hundred thirty-eight million, two hundred eighty-five thousand, four hundred five".