11221997 has 4 divisors (see below), whose sum is σ = 11228736. Its totient is φ = 11215260.

The previous prime is 11221993. The next prime is 11222021. The reversal of 11221997 is 79912211.

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, and also an emirpimes, since its reverse is a distinct semiprime: 79912211 = 809 ⋅98779.

It is a cyclic number.

It is not a de Polignac number, because 11221997 - 2² = 11221993 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11221993) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1148 + ... + 4874.

It is an arithmetic number, because the mean of its divisors is an integer number (2807184).

Almost surely, 2^11221997 is an apocalyptic number.

It is an amenable number.

11221997 is a deficient number, since it is larger than the sum of its proper divisors (6739).

11221997 is an equidigital number, since it uses as much as digits as its factorization.

11221997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6738.

The product of its digits is 2268, while the sum is 32.

The square root of 11221997 is about 3349.9249245319. The cubic root of 11221997 is about 223.8841676315.

The spelling of 11221997 in words is "eleven million, two hundred twenty-one thousand, nine hundred ninety-seven".