21021211222210 has 64 divisors (see below), whose sum is σ = 39291546355200. Its totient is φ = 8087758481152.

The previous prime is 21021211222177. The next prime is 21021211222213. The reversal of 21021211222210 is 1222211212012.

It is not an unprimeable number, because it can be changed into a prime (21021211222213) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 110900196 + ... + 111089584.

It is an arithmetic number, because the mean of its divisors is an integer number (613930411800).

Almost surely, 2^{21021211222210} is an apocalyptic number.

21021211222210 is a deficient number, since it is larger than the sum of its proper divisors (18270335132990).

21021211222210 is a wasteful number, since it uses less digits than its factorization.

21021211222210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190875.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 21021211222210 its reverse (1222211212012), we get a palindrome (22243422434222).

It can be divided in two parts, 2102121 and 1222210, that added together give a triangular number (3324331 = T₂₅₇₈).

The spelling of 21021211222210 in words is "twenty-one trillion, twenty-one billion, two hundred eleven million, two hundred twenty-two thousand, two hundred ten".