138897770 has 32 divisors (see below), whose sum is σ = 275317056. Its totient is φ = 50032000.

The previous prime is 138897751. The next prime is 138897779. The reversal of 138897770 is 77798831.

It is not an unprimeable number, because it can be changed into a prime (138897779) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 5870 + ... + 17670.

It is an arithmetic number, because the mean of its divisors is an integer number (8603658).

Almost surely, 2^138897770 is an apocalyptic number.

138897770 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

138897770 is a deficient number, since it is larger than the sum of its proper divisors (136419286).

138897770 is a wasteful number, since it uses less digits than its factorization.

138897770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11926.

The product of its (nonzero) digits is 592704, while the sum is 50.

The square root of 138897770 is about 11785.4898073860. The cubic root of 138897770 is about 517.8831223612.

The spelling of 138897770 in words is "one hundred thirty-eight million, eight hundred ninety-seven thousand, seven hundred seventy".