138678751 has 2 divisors, whose sum is σ = 138678752. Its totient is φ = 138678750.

The previous prime is 138678731. The next prime is 138678781. The reversal of 138678751 is 157876831.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 138678751 - 2¹³ = 138670559 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (138678731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69339375 + 69339376.

It is an arithmetic number, because the mean of its divisors is an integer number (69339376).

Almost surely, 2^138678751 is an apocalyptic number.

138678751 is a deficient number, since it is larger than the sum of its proper divisors (1).

138678751 is an equidigital number, since it uses as much as digits as its factorization.

138678751 is an evil number, because the sum of its binary digits is even.

The product of its digits is 282240, while the sum is 46.

The square root of 138678751 is about 11776.1942494169. The cubic root of 138678751 is about 517.6107735826.

The spelling of 138678751 in words is "one hundred thirty-eight million, six hundred seventy-eight thousand, seven hundred fifty-one".