11215811 has 2 divisors, whose sum is σ = 11215812. Its totient is φ = 11215810.

The previous prime is 11215781. The next prime is 11215823. The reversal of 11215811 is 11851211.

11215811 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 11215811 - 2¹⁴ = 11199427 is a prime.

It is not a weakly prime, because it can be changed into another prime (11215411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5607905 + 5607906.

It is an arithmetic number, because the mean of its divisors is an integer number (5607906).

Almost surely, 2^11215811 is an apocalyptic number.

11215811 is a deficient number, since it is larger than the sum of its proper divisors (1).

11215811 is an equidigital number, since it uses as much as digits as its factorization.

11215811 is an evil number, because the sum of its binary digits is even.

The product of its digits is 80, while the sum is 20.

The square root of 11215811 is about 3349.0014929826. The cubic root of 11215811 is about 223.8430221914.

The spelling of 11215811 in words is "eleven million, two hundred fifteen thousand, eight hundred eleven".