1000012221 has 12 divisors (see below), whose sum is σ = 1555574748. Its totient is φ = 615392064.

The previous prime is 1000012219. The next prime is 1000012231. The reversal of 1000012221 is 1222100001.

It can be written as a sum of positive squares in 2 ways, for example, as 128936025 + 871076196 = 11355^2 + 29514^2 .

It is not a de Polignac number, because 1000012221 - 2¹ = 1000012219 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1000012231) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4273440 + ... + 4273673.

It is an arithmetic number, because the mean of its divisors is an integer number (129631229).

Almost surely, 2^1000012221 is an apocalyptic number.

It is an amenable number.

1000012221 is a deficient number, since it is larger than the sum of its proper divisors (555562527).

1000012221 is a wasteful number, since it uses less digits than its factorization.

1000012221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8547132 (or 8547129 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 1000012221 is about 31622.9698320699. The cubic root of 1000012221 is about 1000.0040736501.

Adding to 1000012221 its reverse (1222100001), we get a palindrome (2222112222).

The spelling of 1000012221 in words is "one billion, twelve thousand, two hundred twenty-one".