138169161 has 18 divisors (see below), whose sum is σ = 216113118. Its totient is φ = 85026240.

The previous prime is 138169153. The next prime is 138169169. The reversal of 138169161 is 161961831.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (138169153) and next prime (138169169).

It can be written as a sum of positive squares in 3 ways, for example, as 11943936 + 126225225 = 3456^2 + 11235^2 .

It is not a de Polignac number, because 138169161 - 2³ = 138169153 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (138169169) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 43900 + ... + 46941.

Almost surely, 2^138169161 is an apocalyptic number.

It is an amenable number.

138169161 is a deficient number, since it is larger than the sum of its proper divisors (77943957).

138169161 is a wasteful number, since it uses less digits than its factorization.

138169161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90873 (or 90857 counting only the distinct ones).

The product of its digits is 7776, while the sum is 36.

The square root of 138169161 is about 11754.5378896833. The cubic root of 138169161 is about 516.9759899159.

The spelling of 138169161 in words is "one hundred thirty-eight million, one hundred sixty-nine thousand, one hundred sixty-one".