1001122221 has 8 divisors (see below), whose sum is σ = 1456177824. Its totient is φ = 606740720.

The previous prime is 1001122189. The next prime is 1001122229. The reversal of 1001122221 is 1222211001.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1001122221 - 2⁵ = 1001122189 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1001122197 and 1001122206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001122229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15168486 + ... + 15168551.

It is an arithmetic number, because the mean of its divisors is an integer number (182022228).

Almost surely, 2^1001122221 is an apocalyptic number.

1001122221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1001122221 is a deficient number, since it is larger than the sum of its proper divisors (455055603).

1001122221 is a wasteful number, since it uses less digits than its factorization.

1001122221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30337051.

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 1001122221 is about 31640.5154983290. The cubic root of 1001122221 is about 1000.3739338227.

Adding to 1001122221 its reverse (1222211001), we get a palindrome (2223333222).

It can be divided in two parts, 1001 and 122221, that multiplied together give a palindrome (122343221).

The spelling of 1001122221 in words is "one billion, one million, one hundred twenty-two thousand, two hundred twenty-one".