11217477720 has 128 divisors (see below), whose sum is σ = 34805422080. Its totient is φ = 2889216000.

The previous prime is 11217477703. The next prime is 11217477721. The reversal of 11217477720 is 2777471211.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11217477721) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2121480 + ... + 2126760.

It is an arithmetic number, because the mean of its divisors is an integer number (271917360).

Almost surely, 2^11217477720 is an apocalyptic number.

11217477720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11217477720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17402711040).

11217477720 is an abundant number, since it is smaller than the sum of its proper divisors (23587944360).

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

11217477720 is a wasteful number, since it uses less digits than its factorization.

11217477720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5897 (or 5893 counting only the distinct ones).

The product of its (nonzero) digits is 38416, while the sum is 39.

The spelling of 11217477720 in words is "eleven billion, two hundred seventeen million, four hundred seventy-seven thousand, seven hundred twenty".