11821995441 has 21 divisors (see below), whose sum is σ = 17729287401. Its totient is φ = 7879373172.

The previous prime is 11821995407. The next prime is 11821995457. The reversal of 11821995441 is 14459912811.

It is a happy number.

The square root of 11821995441 is 108729.

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

11821995441 is a `hidden beast` number, since 1 + 18 + 2 + 1 + 99 + 544 + 1 = 666.

It is not a de Polignac number, because 11821995441 - 2²¹ = 11819898289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11821995481) by changing a digit.

It is a polite number, since it can be written in 20 ways as a sum of consecutive naturals, for example, 2933670 + ... + 2937696.

It is an arithmetic number, because the mean of its divisors is an integer number (844251781).

Almost surely, 2^11821995441 is an apocalyptic number.

11821995441 is the 108729-th square number.

11821995441 is the 54365-th centered octagonal number.

It is an amenable number.

11821995441 is a deficient number, since it is larger than the sum of its proper divisors (5907291960).

11821995441 is an frugal number, since it uses more digits than its factorization.

11821995441 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8072 (or 4030 counting only the distinct ones).

The product of its digits is 103680, while the sum is 45.

The spelling of 11821995441 in words is "eleven billion, eight hundred twenty-one million, nine hundred ninety-five thousand, four hundred forty-one".