138539563 has 2 divisors, whose sum is σ = 138539564. Its totient is φ = 138539562.

The previous prime is 138539561. The next prime is 138539617. The reversal of 138539563 is 365935831.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 138539563 - 2¹ = 138539561 is a prime.

Together with 138539561, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (138539561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69269781 + 69269782.

It is an arithmetic number, because the mean of its divisors is an integer number (69269782).

Almost surely, 2^138539563 is an apocalyptic number.

138539563 is a deficient number, since it is larger than the sum of its proper divisors (1).

138539563 is an equidigital number, since it uses as much as digits as its factorization.

138539563 is an evil number, because the sum of its binary digits is even.

The product of its digits is 291600, while the sum is 43.

The square root of 138539563 is about 11770.2830467241. The cubic root of 138539563 is about 517.4375451090.

The spelling of 138539563 in words is "one hundred thirty-eight million, five hundred thirty-nine thousand, five hundred sixty-three".