1001212121 has 8 divisors (see below), whose sum is σ = 1232261184. Its totient is φ = 792167760.

The previous prime is 1001212111. The next prime is 1001212181. The reversal of 1001212121 is 1212121001.

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 1001212121 - 2²⁶ = 934103257 is a prime.

It is a super-2 number, since 2×1001212121² = 2004851422474637282, which contains 22 as substring.

1001212121 is a modest number, since divided by 212121 gives 1001 as remainder.

It is not an unprimeable number, because it can be changed into a prime (1001212111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5501075 + ... + 5501256.

It is an arithmetic number, because the mean of its divisors is an integer number (154032648).

Almost surely, 2^1001212121 is an apocalyptic number.

It is an amenable number.

1001212121 is a deficient number, since it is larger than the sum of its proper divisors (231049063).

1001212121 is a wasteful number, since it uses less digits than its factorization.

1001212121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11002351.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 1001212121 is about 31641.9361133291. The cubic root of 1001212121 is about 1000.4038771946.

Adding to 1001212121 its reverse (1212121001), we get a palindrome (2213333122).

The spelling of 1001212121 in words is "one billion, one million, two hundred twelve thousand, one hundred twenty-one".