138763881 has 32 divisors (see below), whose sum is σ = 214917120. Its totient is φ = 88400592.

The previous prime is 138763879. The next prime is 138763903. The reversal of 138763881 is 188367831.

138763881 is a `hidden beast` number, since 1 + 3 + 8 + 7 + 638 + 8 + 1 = 666.

It is not a de Polignac number, because 138763881 - 2¹ = 138763879 is a prime.

It is a super-2 number, since 2×138763881² = 38510829340364322, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (138762881) 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 in 31 ways as a sum of consecutive naturals, for example, 53296 + ... + 55838.

It is an arithmetic number, because the mean of its divisors is an integer number (6716160).

Almost surely, 2^138763881 is an apocalyptic number.

It is an amenable number.

138763881 is a deficient number, since it is larger than the sum of its proper divisors (76153239).

138763881 is a wasteful number, since it uses less digits than its factorization.

138763881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2642 (or 2636 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 138763881 is about 11779.8081902890. The cubic root of 138763881 is about 517.7166662576.

The spelling of 138763881 in words is "one hundred thirty-eight million, seven hundred sixty-three thousand, eight hundred eighty-one".