11715220 has 72 divisors (see below), whose sum is σ = 27885312. Its totient is φ = 4128960.

The previous prime is 11715203. The next prime is 11715239. The reversal of 11715220 is 2251711.

11715220 = T₁₅₆ + T₁₅₇ + ... + T₄₁₉.

11715220 is a nontrivial binomial coefficient, being equal to C(4841, 2).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 113689 + ... + 113791.

It is an arithmetic number, because the mean of its divisors is an integer number (387296).

Almost surely, 2^11715220 is an apocalyptic number.

11715220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

11715220 is the 4840-th triangular number.

11715220 is the 1614-th centered nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 11715220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13942656).

11715220 is an abundant number, since it is smaller than the sum of its proper divisors (16170092).

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

11715220 is a wasteful number, since it uses less digits than its factorization.

11715220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181 (or 168 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 19.

The square root of 11715220 is about 3422.7503560733. The cubic root of 11715220 is about 227.1172649312.

Adding to 11715220 its reverse (2251711), we get a palindrome (13966931).

It can be divided in two parts, 11715 and 220, that added together give a triangular number (11935 = T₁₅₄).

The spelling of 11715220 in words is "eleven million, seven hundred fifteen thousand, two hundred twenty".