11220991 has 2 divisors, whose sum is σ = 11220992. Its totient is φ = 11220990.

The previous prime is 11220931. The next prime is 11220997. The reversal of 11220991 is 19902211.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 11220991 - 2¹¹ = 11218943 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11220997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5610495 + 5610496.

It is an arithmetic number, because the mean of its divisors is an integer number (5610496).

Almost surely, 2^11220991 is an apocalyptic number.

11220991 is a deficient number, since it is larger than the sum of its proper divisors (1).

11220991 is an equidigital number, since it uses as much as digits as its factorization.

11220991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 25.

The square root of 11220991 is about 3349.7747685479. The cubic root of 11220991 is about 223.8774773724.

The spelling of 11220991 in words is "eleven million, two hundred twenty thousand, nine hundred ninety-one".