138223221 has 8 divisors (see below), whose sum is σ = 184386624. Its totient is φ = 92104320.

The previous prime is 138223181. The next prime is 138223291. The reversal of 138223221 is 122322831.

It is a happy number.

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

It is not a de Polignac number, because 138223221 - 2¹⁰ = 138222197 is a prime.

It is a super-2 number, since 2×138223221² = 38211317647229682, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 138223191 and 138223200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (138223291) 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, 3036 + ... + 16901.

It is an arithmetic number, because the mean of its divisors is an integer number (23048328).

Almost surely, 2^138223221 is an apocalyptic number.

It is an amenable number.

138223221 is a deficient number, since it is larger than the sum of its proper divisors (46163403).

138223221 is a wasteful number, since it uses less digits than its factorization.

138223221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22251.

The product of its digits is 1152, while the sum is 24.

The square root of 138223221 is about 11756.8372022411. The cubic root of 138223221 is about 517.0434050508.

The spelling of 138223221 in words is "one hundred thirty-eight million, two hundred twenty-three thousand, two hundred twenty-one".