991226 has 4 divisors (see below), whose sum is σ = 1486842. Its totient is φ = 495612.

The previous prime is 991223. The next prime is 991229. The reversal of 991226 is 622199.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 622199 = 89 ⋅6991.

It is an interprime number because it is at equal distance from previous prime (991223) and next prime (991229).

It can be written as a sum of positive squares in only one way, i.e., 570025 + 421201 = 755^2 + 649^2 .

It is not an unprimeable number, because it can be changed into a prime (991223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 247805 + ... + 247808.

2⁹⁹¹²²⁶ is an apocalyptic number.

991226 is a deficient number, since it is larger than the sum of its proper divisors (495616).

991226 is a wasteful number, since it uses less digits than its factorization.

991226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 495615.

The product of its digits is 1944, while the sum is 29.

The square root of 991226 is about 995.6033346670. The cubic root of 991226 is about 99.7066737718.

The spelling of 991226 in words is "nine hundred ninety-one thousand, two hundred twenty-six".