21012201210 has 256 divisors, whose sum is σ = 69542903808. Its totient is φ = 3921177600.

The previous prime is 21012201113. The next prime is 21012201211. The reversal of 21012201210 is 1210221012.

It is not an unprimeable number, because it can be changed into a prime (21012201211) 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, 1101655 + ... + 1120565.

It is an arithmetic number, because the mean of its divisors is an integer number (271651968).

Almost surely, 2^21012201210 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21012201210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34771451904).

21012201210 is an abundant number, since it is smaller than the sum of its proper divisors (48530702598).

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

21012201210 is a wasteful number, since it uses less digits than its factorization.

21012201210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18989.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21012201210 its reverse (1210221012), we get a palindrome (22222422222).

It can be divided in two parts, 21012 and 201210, that added together give a palindrome (222222).

The spelling of 21012201210 in words is "twenty-one billion, twelve million, two hundred one thousand, two hundred ten".