138940785 has 16 divisors (see below), whose sum is σ = 247006080. Its totient is φ = 74101680.

The previous prime is 138940771. The next prime is 138940807. The reversal of 138940785 is 587049831.

It is not a de Polignac number, because 138940785 - 2⁶ = 138940721 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 138940785.

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, 514461 + ... + 514730.

It is an arithmetic number, because the mean of its divisors is an integer number (15437880).

Almost surely, 2^138940785 is an apocalyptic number.

138940785 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

138940785 is a deficient number, since it is larger than the sum of its proper divisors (108065295).

138940785 is a wasteful number, since it uses less digits than its factorization.

138940785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1029205 (or 1029199 counting only the distinct ones).

The product of its (nonzero) digits is 241920, while the sum is 45.

The square root of 138940785 is about 11787.3145796657. The cubic root of 138940785 is about 517.9365776070.

The spelling of 138940785 in words is "one hundred thirty-eight million, nine hundred forty thousand, seven hundred eighty-five".