138601987 has 2 divisors, whose sum is σ = 138601988. Its totient is φ = 138601986.

The previous prime is 138601937. The next prime is 138601999. The reversal of 138601987 is 789106831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138601987 - 2¹¹ = 138599939 is a prime.

It is a plaindrome in base 14.

It is not a weakly prime, because it can be changed into another prime (138601907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69300993 + 69300994.

It is an arithmetic number, because the mean of its divisors is an integer number (69300994).

Almost surely, 2^138601987 is an apocalyptic number.

138601987 is a deficient number, since it is larger than the sum of its proper divisors (1).

138601987 is an equidigital number, since it uses as much as digits as its factorization.

138601987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72576, while the sum is 43.

The square root of 138601987 is about 11772.9345109875. The cubic root of 138601987 is about 517.5152501593.

The spelling of 138601987 in words is "one hundred thirty-eight million, six hundred one thousand, nine hundred eighty-seven".