138777764 has 6 divisors (see below), whose sum is σ = 242861094. Its totient is φ = 69388880.

The previous prime is 138777761. The next prime is 138777773. The reversal of 138777764 is 467777831.

It can be written as a sum of positive squares in only one way, i.e., 71537764 + 67240000 = 8458^2 + 8200^2 .

It is not an unprimeable number, because it can be changed into a prime (138777761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 17347217 + ... + 17347224.

It is an arithmetic number, because the mean of its divisors is an integer number (40476849).

Almost surely, 2^138777764 is an apocalyptic number.

It is an amenable number.

138777764 is a deficient number, since it is larger than the sum of its proper divisors (104083330).

138777764 is a wasteful number, since it uses less digits than its factorization.

138777764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34694445 (or 34694443 counting only the distinct ones).

The product of its digits is 1382976, while the sum is 50.

The square root of 138777764 is about 11780.3974466060. The cubic root of 138777764 is about 517.7339311269.

The spelling of 138777764 in words is "one hundred thirty-eight million, seven hundred seventy-seven thousand, seven hundred sixty-four".