1021000021011 has 12 divisors (see below), whose sum is σ = 1529399208792. Its totient is φ = 680666680512.

The previous prime is 1021000021007. The next prime is 1021000021087. The reversal of 1021000021011 is 1101200001201.

It is a happy number.

It is not a de Polignac number, because 1021000021011 - 2² = 1021000021007 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 1021000020984 and 1021000021002.

It is not an unprimeable number, because it can be changed into a prime (1021000020011) 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 11 ways as a sum of consecutive naturals, for example, 2100822846 + ... + 2100823331.

It is an arithmetic number, because the mean of its divisors is an integer number (127449934066).

Almost surely, 2^{1021000021011} is an apocalyptic number.

1021000021011 is a deficient number, since it is larger than the sum of its proper divisors (508399187781).

1021000021011 is an frugal number, since it uses more digits than its factorization.

1021000021011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4201646192 (or 4201646180 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 1021000021011 its reverse (1101200001201), we get a palindrome (2122200022212).

The spelling of 1021000021011 in words is "one trillion, twenty-one billion, twenty-one thousand, eleven".