1001212221 has 8 divisors (see below), whose sum is σ = 1347910720. Its totient is φ = 660994272.

The previous prime is 1001212217. The next prime is 1001212231. The reversal of 1001212221 is 1222121001.

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

It is not a de Polignac number, because 1001212221 - 2² = 1001212217 is a prime.

It is a super-2 number, since 2×1001212221² = 2004851822959505682, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1001212197 and 1001212206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001212231) 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, 1619776 + ... + 1620393.

It is an arithmetic number, because the mean of its divisors is an integer number (168488840).

Almost surely, 2^1001212221 is an apocalyptic number.

It is an amenable number.

1001212221 is a deficient number, since it is larger than the sum of its proper divisors (346698499).

1001212221 is a wasteful number, since it uses less digits than its factorization.

1001212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3240275.

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

The square root of 1001212221 is about 31641.9376935105. The cubic root of 1001212221 is about 1000.4039105010.

Adding to 1001212221 its reverse (1222121001), we get a palindrome (2223333222).

The spelling of 1001212221 in words is "one billion, one million, two hundred twelve thousand, two hundred twenty-one".