9211138 has 4 divisors (see below), whose sum is σ = 13816710. Its totient is φ = 4605568.

The previous prime is 9211133. The next prime is 9211141. The reversal of 9211138 is 8311129.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8311129 = 479 ⋅17351.

It can be written as a sum of positive squares in only one way, i.e., 6692569 + 2518569 = 2587^2 + 1587^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9211133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2302783 + ... + 2302786.

Almost surely, 2^9211138 is an apocalyptic number.

9211138 is a deficient number, since it is larger than the sum of its proper divisors (4605572).

9211138 is a wasteful number, since it uses less digits than its factorization.

9211138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4605571.

The product of its digits is 432, while the sum is 25.

The square root of 9211138 is about 3034.9856671820. The cubic root of 9211138 is about 209.6224357090.

Subtracting from 9211138 its reverse (8311129), we obtain a palindrome (900009).

The spelling of 9211138 in words is "nine million, two hundred eleven thousand, one hundred thirty-eight".