1001211100021 has 6 divisors (see below), whose sum is σ = 1100504762966. Its totient is φ = 910191909000.

The previous prime is 1001211100009. The next prime is 1001211100031. The reversal of 1001211100021 is 1200011121001.

It can be written as a sum of positive squares in only one way, i.e., 505749967921 + 495461132100 = 711161^2 + 703890^2 .

It is not a de Polignac number, because 1001211100021 - 2⁵ = 1001211099989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1001211099980 and 1001211100007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001211100031) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4137235830 + ... + 4137236071.

Almost surely, 2^{1001211100021} is an apocalyptic number.

1001211100021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1001211100021 is a deficient number, since it is larger than the sum of its proper divisors (99293662945).

1001211100021 is an equidigital number, since it uses as much as digits as its factorization.

1001211100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8274471923 (or 8274471912 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 1001211100021 its reverse (1200011121001), we get a palindrome (2201222221022).

The spelling of 1001211100021 in words is "one trillion, one billion, two hundred eleven million, one hundred thousand, twenty-one".