138256161 has 8 divisors (see below), whose sum is σ = 189323904. Its totient is φ = 89679600.

The previous prime is 138256159. The next prime is 138256163. The reversal of 138256161 is 161652831.

138256161 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (138256159) and next prime (138256163).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 138256161 - 2¹ = 138256159 is a prime.

It is a super-2 number, since 2×138256161² = 38229532108915842, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (138256163) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 622665 + ... + 622886.

It is an arithmetic number, because the mean of its divisors is an integer number (23665488).

Almost surely, 2^138256161 is an apocalyptic number.

It is an amenable number.

138256161 is a deficient number, since it is larger than the sum of its proper divisors (51067743).

138256161 is a wasteful number, since it uses less digits than its factorization.

138256161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1245591.

The product of its digits is 8640, while the sum is 33.

The square root of 138256161 is about 11758.2380057558. The cubic root of 138256161 is about 517.0844740233.

The spelling of 138256161 in words is "one hundred thirty-eight million, two hundred fifty-six thousand, one hundred sixty-one".