1001011212121 has 4 divisors (see below), whose sum is σ = 1001015971200. Its totient is φ = 1001006453044.

The previous prime is 1001011212107. The next prime is 1001011212163. The reversal of 1001011212121 is 1212121101001.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1001011212121 - 2³⁷ = 863572258649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1001011612121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2048701 + ... + 2489818.

It is an arithmetic number, because the mean of its divisors is an integer number (250253992800).

Almost surely, 2^{1001011212121} is an apocalyptic number.

It is an amenable number.

1001011212121 is a deficient number, since it is larger than the sum of its proper divisors (4759079).

1001011212121 is an equidigital number, since it uses as much as digits as its factorization.

1001011212121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4759078.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 1001011212121 its reverse (1212121101001), we get a palindrome (2213132313122).

The spelling of 1001011212121 in words is "one trillion, one billion, eleven million, two hundred twelve thousand, one hundred twenty-one".