138687851 has 2 divisors, whose sum is σ = 138687852. Its totient is φ = 138687850.

The previous prime is 138687839. The next prime is 138687869. The reversal of 138687851 is 158786831.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 138687851 - 2¹⁰ = 138686827 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 138687796 and 138687805.

It is not a weakly prime, because it can be changed into another prime (138687551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69343925 + 69343926.

It is an arithmetic number, because the mean of its divisors is an integer number (69343926).

Almost surely, 2^138687851 is an apocalyptic number.

138687851 is a deficient number, since it is larger than the sum of its proper divisors (1).

138687851 is an equidigital number, since it uses as much as digits as its factorization.

138687851 is an evil number, because the sum of its binary digits is even.

The product of its digits is 322560, while the sum is 47.

The square root of 138687851 is about 11776.5806157815. The cubic root of 138687851 is about 517.6220950840.

The spelling of 138687851 in words is "one hundred thirty-eight million, six hundred eighty-seven thousand, eight hundred fifty-one".