8001221131 has 4 divisors (see below), whose sum is σ = 8010043672. Its totient is φ = 7992398592.

The previous prime is 8001221113. The next prime is 8001221153. The reversal of 8001221131 is 1311221008.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 8001221131 - 2²⁵ = 7967666699 is a prime.

It is a super-2 number, since 2×8001221131² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 8001221099 and 8001221108.

It is not an unprimeable number, because it can be changed into a prime (8001221231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4409910 + ... + 4411723.

It is an arithmetic number, because the mean of its divisors is an integer number (2002510918).

Almost surely, 2^8001221131 is an apocalyptic number.

8001221131 is a deficient number, since it is larger than the sum of its proper divisors (8822541).

8001221131 is an equidigital number, since it uses as much as digits as its factorization.

8001221131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8822540.

The product of its (nonzero) digits is 96, while the sum is 19.

The square root of 8001221131 is about 89449.5451693300. The cubic root of 8001221131 is about 2000.1017557395.

Adding to 8001221131 its reverse (1311221008), we get a palindrome (9312442139).

The spelling of 8001221131 in words is "eight billion, one million, two hundred twenty-one thousand, one hundred thirty-one".