11217720 has 32 divisors (see below), whose sum is σ = 33653520. Its totient is φ = 2991360.

The previous prime is 11217683. The next prime is 11217737. The reversal of 11217720 is 2771211.

It is a happy number.

11217720 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 46621 + ... + 46860.

Almost surely, 2^11217720 is an apocalyptic number.

11217720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11217720 is an abundant number, since it is smaller than the sum of its proper divisors (22435800).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11217720 is a wasteful number, since it uses less digits than its factorization.

11217720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93495 (or 93491 counting only the distinct ones).

The product of its (nonzero) digits is 196, while the sum is 21.

The square root of 11217720 is about 3349.2864911799. The cubic root of 11217720 is about 223.8557212905.

Adding to 11217720 its reverse (2771211), we get a palindrome (13988931).

The spelling of 11217720 in words is "eleven million, two hundred seventeen thousand, seven hundred twenty".