21020121001012 has 24 divisors (see below), whose sum is σ = 44252886319040. Its totient is φ = 8534485218240.

The previous prime is 21020121000979. The next prime is 21020121001013. The reversal of 21020121001012 is 21010012102012.

It is a junction number, because it is equal to n+sod(n) for n = 21020121000983 and 21020121001001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21020121001013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19755752289 + ... + 19755753352.

Almost surely, 2^{21020121001012} is an apocalyptic number.

It is an amenable number.

21020121001012 is an abundant number, since it is smaller than the sum of its proper divisors (23232765318028).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21020121001012 is a wasteful number, since it uses less digits than its factorization.

21020121001012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39511505671 (or 39511505669 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21020121001012 its reverse (21010012102012), we get a palindrome (42030133103024).

The spelling of 21020121001012 in words is "twenty-one trillion, twenty billion, one hundred twenty-one million, one thousand, twelve".