1001211121021 has 4 divisors (see below), whose sum is σ = 1053906443200. Its totient is φ = 948515798844.

The previous prime is 1001211121007. The next prime is 1001211121103. The reversal of 1001211121021 is 1201211121001.

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 1001211121021 - 2¹⁵ = 1001211088253 is a prime.

It is a super-2 number, since 2×1001211121021² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1001211120992 and 1001211121010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001211121321) 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, 26347661061 + ... + 26347661098.

It is an arithmetic number, because the mean of its divisors is an integer number (263476610800).

Almost surely, 2^{1001211121021} is an apocalyptic number.

It is an amenable number.

1001211121021 is a deficient number, since it is larger than the sum of its proper divisors (52695322179).

1001211121021 is an equidigital number, since it uses as much as digits as its factorization.

1001211121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52695322178.

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

Adding to 1001211121021 its reverse (1201211121001), we get a palindrome (2202422242022).

The spelling of 1001211121021 in words is "one trillion, one billion, two hundred eleven million, one hundred twenty-one thousand, twenty-one".