11171221636 has 27 divisors (see below), whose sum is σ = 20031152421. Its totient is φ = 5451273744.

The previous prime is 11171221591. The next prime is 11171221643. The reversal of 11171221636 is 63612217111.

The square root of 11171221636 is 105694.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 11026260036 + 144961600 = 105006^2 + 12040^2 .

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11171221598 and 11171221607.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 9089070 + ... + 9090298.

Almost surely, 2^11171221636 is an apocalyptic number.

11171221636 is the 105694-th square number.

It is an amenable number.

11171221636 is a deficient number, since it is larger than the sum of its proper divisors (8859930785).

11171221636 is an frugal number, since it uses more digits than its factorization.

11171221636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2548 (or 1274 counting only the distinct ones).

The product of its digits is 3024, while the sum is 31.

Adding to 11171221636 its reverse (63612217111), we get a palindrome (74783438747).

The spelling of 11171221636 in words is "eleven billion, one hundred seventy-one million, two hundred twenty-one thousand, six hundred thirty-six".