138395281 has 16 divisors (see below), whose sum is σ = 145555200. Its totient is φ = 131459328.

The previous prime is 138395269. The next prime is 138395291. The reversal of 138395281 is 182593831.

It is a cyclic number.

It is not a de Polignac number, because 138395281 - 2¹⁷ = 138264209 is a prime.

It is a super-2 number, since 2×138395281² = 38306507606137922, which contains 22 as substring.

It is a Duffinian number.

Its product of digits (51840) is a multiple of the sum of its prime divisors (648).

It is not an unprimeable number, because it can be changed into a prime (138395291) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 330090 + ... + 330508.

It is an arithmetic number, because the mean of its divisors is an integer number (9097200).

Almost surely, 2^138395281 is an apocalyptic number.

It is an amenable number.

138395281 is a deficient number, since it is larger than the sum of its proper divisors (7159919).

138395281 is a wasteful number, since it uses less digits than its factorization.

138395281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 648.

The product of its digits is 51840, while the sum is 40.

The square root of 138395281 is about 11764.1523706555. The cubic root of 138395281 is about 517.2578543058.

The spelling of 138395281 in words is "one hundred thirty-eight million, three hundred ninety-five thousand, two hundred eighty-one".