21011121210102 has 64 divisors (see below), whose sum is σ = 43880225541120. Its totient is φ = 6698594690816.

The previous prime is 21011121210071. The next prime is 21011121210103. The reversal of 21011121210102 is 20101212111012.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011121210103) 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 31 ways as a sum of consecutive naturals, for example, 510242938 + ... + 510284114.

It is an arithmetic number, because the mean of its divisors is an integer number (685628524080).

Almost surely, 2^{21011121210102} is an apocalyptic number.

21011121210102 is an abundant number, since it is smaller than the sum of its proper divisors (22869104331018).

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

21011121210102 is a wasteful number, since it uses less digits than its factorization.

21011121210102 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68725.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21011121210102 its reverse (20101212111012), we get a palindrome (41112333321114).

The spelling of 21011121210102 in words is "twenty-one trillion, eleven billion, one hundred twenty-one million, two hundred ten thousand, one hundred two".