1001311221 has 16 divisors (see below), whose sum is σ = 1343574144. Its totient is φ = 663308544.

The previous prime is 1001311211. The next prime is 1001311247. The reversal of 1001311221 is 1221131001.

It is not a de Polignac number, because 1001311221 - 2⁵ = 1001311189 is a prime.

It is a super-2 number, since 2×1001311221² = 2005248322601021682, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1001311197 and 1001311206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001311211) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 359185 + ... + 361961.

It is an arithmetic number, because the mean of its divisors is an integer number (83973384).

Almost surely, 2^1001311221 is an apocalyptic number.

It is an amenable number.

1001311221 is a deficient number, since it is larger than the sum of its proper divisors (342262923).

1001311221 is a wasteful number, since it uses less digits than its factorization.

1001311221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3500.

The product of its (nonzero) digits is 12, while the sum is 12.

The square root of 1001311221 is about 31643.5020343830. The cubic root of 1001311221 is about 1000.4368827723.

Adding to 1001311221 its reverse (1221131001), we get a palindrome (2222442222).

The spelling of 1001311221 in words is "one billion, one million, three hundred eleven thousand, two hundred twenty-one".