21010020121010 has 32 divisors (see below), whose sum is σ = 40245888711600. Its totient is φ = 7869504090112.

The previous prime is 21010020120989. The next prime is 21010020121067. The reversal of 21010020121010 is 1012102001012.

It can be written as a sum of positive squares in 8 ways, for example, as 16810729807921 + 4199290313089 = 4100089^2 + 2049217^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21010020120982 and 21010020121000.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 313642535 + ... + 313709514.

Almost surely, 2^{21010020121010} is an apocalyptic number.

21010020121010 is a deficient number, since it is larger than the sum of its proper divisors (19235868590590).

21010020121010 is a wasteful number, since it uses less digits than its factorization.

21010020121010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 627352270.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21010020121010 its reverse (1012102001012), we get a palindrome (22022122122022).

The spelling of 21010020121010 in words is "twenty-one trillion, ten billion, twenty million, one hundred twenty-one thousand, ten".