1001120221 has 4 divisors (see below), whose sum is σ = 1001442492. Its totient is φ = 1000797952.

The previous prime is 1001120213. The next prime is 1001120243. The reversal of 1001120221 is 1220211001.

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

It can be written as a sum of positive squares in 2 ways, for example, as 581484996 + 419635225 = 24114^2 + 20485^2 .

It is a cyclic number.

It is not a de Polignac number, because 1001120221 - 2³ = 1001120213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1001120198 and 1001120207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001120261) 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, 156430 + ... + 162703.

It is an arithmetic number, because the mean of its divisors is an integer number (250360623).

Almost surely, 2^1001120221 is an apocalyptic number.

It is an amenable number.

1001120221 is a deficient number, since it is larger than the sum of its proper divisors (322271).

1001120221 is an equidigital number, since it uses as much as digits as its factorization.

1001120221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322270.

The product of its (nonzero) digits is 8, while the sum is 10.

The square root of 1001120221 is about 31640.4838932656. The cubic root of 1001120221 is about 1000.3732676539.

Adding to 1001120221 its reverse (1220211001), we get a palindrome (2221331222).

The spelling of 1001120221 in words is "one billion, one million, one hundred twenty thousand, two hundred twenty-one".