138761587 has 2 divisors, whose sum is σ = 138761588. Its totient is φ = 138761586.

The previous prime is 138761561. The next prime is 138761603. The reversal of 138761587 is 785167831.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 138761587 - 2⁷ = 138761459 is a prime.

It is not a weakly prime, because it can be changed into another prime (138761537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69380793 + 69380794.

It is an arithmetic number, because the mean of its divisors is an integer number (69380794).

Almost surely, 2^138761587 is an apocalyptic number.

138761587 is a deficient number, since it is larger than the sum of its proper divisors (1).

138761587 is an equidigital number, since it uses as much as digits as its factorization.

138761587 is an odious number, because the sum of its binary digits is odd.

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

The square root of 138761587 is about 11779.7108198801. The cubic root of 138761587 is about 517.7138133332.

It can be divided in two parts, 13 and 8761587, that added together give a square (8761600 = 2960²).

The spelling of 138761587 in words is "one hundred thirty-eight million, seven hundred sixty-one thousand, five hundred eighty-seven".