11771821225 has 12 divisors (see below), whose sum is σ = 14797020316. Its totient is φ = 9288449280.

The previous prime is 11771821223. The next prime is 11771821273. The reversal of 11771821225 is 52212817711.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 297769536 + 11474051689 = 17256^2 + 107117^2 .

It is not a de Polignac number, because 11771821225 - 2¹ = 11771821223 is a prime.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11771821223) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3223332 + ... + 3226981.

Almost surely, 2^11771821225 is an apocalyptic number.

It is an amenable number.

11771821225 is a deficient number, since it is larger than the sum of its proper divisors (3025199091).

11771821225 is an equidigital number, since it uses as much as digits as its factorization.

11771821225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6450396 (or 6450391 counting only the distinct ones).

The product of its digits is 15680, while the sum is 37.

The spelling of 11771821225 in words is "eleven billion, seven hundred seventy-one million, eight hundred twenty-one thousand, two hundred twenty-five".