21021122221210 has 256 divisors, whose sum is σ = 41368186252800. Its totient is φ = 7674225721344.

The previous prime is 21021122221189. The next prime is 21021122221217. The reversal of 21021122221210 is 1212222112012.

It is not an unprimeable number, because it can be changed into a prime (21021122221217) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 16207495282 + ... + 16207496578.

It is an arithmetic number, because the mean of its divisors is an integer number (161594477550).

Almost surely, 2^{21021122221210} is an apocalyptic number.

21021122221210 is a deficient number, since it is larger than the sum of its proper divisors (20347064031590).

21021122221210 is a wasteful number, since it uses less digits than its factorization.

21021122221210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1745.

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

Adding to 21021122221210 its reverse (1212222112012), we get a palindrome (22233344333222).

The spelling of 21021122221210 in words is "twenty-one trillion, twenty-one billion, one hundred twenty-two million, two hundred twenty-one thousand, two hundred ten".