138780671 has 2 divisors, whose sum is σ = 138780672. Its totient is φ = 138780670.

The previous prime is 138780559. The next prime is 138780701. The reversal of 138780671 is 176087831.

It is a strong prime.

It is an emirp because it is prime and its reverse (176087831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 138780671 - 2¹⁰ = 138779647 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138780071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69390335 + 69390336.

It is an arithmetic number, because the mean of its divisors is an integer number (69390336).

Almost surely, 2^138780671 is an apocalyptic number.

138780671 is a deficient number, since it is larger than the sum of its proper divisors (1).

138780671 is an equidigital number, since it uses as much as digits as its factorization.

138780671 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56448, while the sum is 41.

The square root of 138780671 is about 11780.5208288938. The cubic root of 138780671 is about 517.7375461201.

The spelling of 138780671 in words is "one hundred thirty-eight million, seven hundred eighty thousand, six hundred seventy-one".