138065631 has 32 divisors (see below), whose sum is σ = 206343936. Its totient is φ = 81408000.

The previous prime is 138065621. The next prime is 138065659. The reversal of 138065631 is 136560831.

It is not a de Polignac number, because 138065631 - 2⁶ = 138065567 is a prime.

It is a super-2 number, since 2×138065631² = 38124236926856322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a junction number, because it is equal to n+sod(n) for n = 138065592 and 138065601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138065621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 215071 + ... + 215711.

It is an arithmetic number, because the mean of its divisors is an integer number (6448248).

Almost surely, 2^138065631 is an apocalyptic number.

138065631 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

138065631 is a deficient number, since it is larger than the sum of its proper divisors (68278305).

138065631 is a wasteful number, since it uses less digits than its factorization.

138065631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 823.

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 138065631 is about 11750.1332332872. The cubic root of 138065631 is about 516.8468344721.

The spelling of 138065631 in words is "one hundred thirty-eight million, sixty-five thousand, six hundred thirty-one".