2121121011001 has 4 divisors (see below), whose sum is σ = 2140580836900. Its totient is φ = 2101661185104.

The previous prime is 2121121010999. The next prime is 2121121011017. The reversal of 2121121011001 is 1001101211212.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1651314951225 + 469806059776 = 1285035^2 + 685424^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121121011001 - 2¹ = 2121121010999 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2121121015001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9729912786 + ... + 9729913003.

It is an arithmetic number, because the mean of its divisors is an integer number (535145209225).

Almost surely, 2^{2121121011001} is an apocalyptic number.

It is an amenable number.

2121121011001 is a deficient number, since it is larger than the sum of its proper divisors (19459825899).

2121121011001 is a wasteful number, since it uses less digits than its factorization.

2121121011001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19459825898.

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

Adding to 2121121011001 its reverse (1001101211212), we get a palindrome (3122222222213).

The spelling of 2121121011001 in words is "two trillion, one hundred twenty-one billion, one hundred twenty-one million, eleven thousand, one".