138866263 has 4 divisors (see below), whose sum is σ = 139003560. Its totient is φ = 138728968.

The previous prime is 138866243. The next prime is 138866281. The reversal of 138866263 is 362668831.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 138866263 - 2⁹ = 138865751 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138866243) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67120 + ... + 69157.

It is an arithmetic number, because the mean of its divisors is an integer number (34750890).

Almost surely, 2^138866263 is an apocalyptic number.

138866263 is a deficient number, since it is larger than the sum of its proper divisors (137297).

138866263 is a wasteful number, since it uses less digits than its factorization.

138866263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137296.

The product of its digits is 248832, while the sum is 43.

The square root of 138866263 is about 11784.1530455099. The cubic root of 138866263 is about 517.8439612395.

It can be divided in two parts, 138866 and 263, that added together give a square (139129 = 373²).

The spelling of 138866263 in words is "one hundred thirty-eight million, eight hundred sixty-six thousand, two hundred sixty-three".