21021210211210 has 96 divisors (see below), whose sum is σ = 44162004869136. Its totient is φ = 7174041600000.

The previous prime is 21021210211189. The next prime is 21021210211213. The reversal of 21021210211210 is 1211201212012.

It can be written as a sum of positive squares in 8 ways, for example, as 18033093478521 + 2988116732689 = 4246539^2 + 1728617^2 .

It is not an unprimeable number, because it can be changed into a prime (21021210211213) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5813710 + ... + 8708710.

Almost surely, 2^{21021210211210} is an apocalyptic number.

21021210211210 is an abundant number, since it is smaller than the sum of its proper divisors (23140794657926).

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

21021210211210 is a wasteful number, since it uses less digits than its factorization.

21021210211210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2895400 (or 2895389 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21021210211210 its reverse (1211201212012), we get a palindrome (22232411423222).

The spelling of 21021210211210 in words is "twenty-one trillion, twenty-one billion, two hundred ten million, two hundred eleven thousand, two hundred ten".