138962281 has 4 divisors (see below), whose sum is σ = 138986064. Its totient is φ = 138938500.

The previous prime is 138962273. The next prime is 138962293. The reversal of 138962281 is 182269831.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 138962281 - 2³ = 138962273 is a prime.

It is a super-2 number, since 2×138962281² = 38621031081445922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138962231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3606 + ... + 17056.

It is an arithmetic number, because the mean of its divisors is an integer number (34746516).

Almost surely, 2^138962281 is an apocalyptic number.

It is an amenable number.

138962281 is a deficient number, since it is larger than the sum of its proper divisors (23783).

138962281 is a wasteful number, since it uses less digits than its factorization.

138962281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23782.

The product of its digits is 41472, while the sum is 40.

The square root of 138962281 is about 11788.2263721053. The cubic root of 138962281 is about 517.9632868044.

The spelling of 138962281 in words is "one hundred thirty-eight million, nine hundred sixty-two thousand, two hundred eighty-one".