138777806 has 16 divisors (see below), whose sum is σ = 212569728. Its totient is φ = 67932000.

The previous prime is 138777781. The next prime is 138777833. The reversal of 138777806 is 608777831.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24656 + ... + 29756.

It is an arithmetic number, because the mean of its divisors is an integer number (13285608).

Almost surely, 2^138777806 is an apocalyptic number.

138777806 is a deficient number, since it is larger than the sum of its proper divisors (73791922).

138777806 is a wasteful number, since it uses less digits than its factorization.

138777806 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5387.

The product of its (nonzero) digits is 395136, while the sum is 47.

The square root of 138777806 is about 11780.3992292282. The cubic root of 138777806 is about 517.7339833562.

The spelling of 138777806 in words is "one hundred thirty-eight million, seven hundred seventy-seven thousand, eight hundred six".