21011101210 has 32 divisors (see below), whose sum is σ = 43685116992. Its totient is φ = 7190964480.

The previous prime is 21011101207. The next prime is 21011101217. The reversal of 21011101210 is 1210111012.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is not an unprimeable number, because it can be changed into a prime (21011101217) 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 15 ways as a sum of consecutive naturals, for example, 5616072 + ... + 5619811.

It is an arithmetic number, because the mean of its divisors is an integer number (1365159906).

Almost surely, 2^21011101210 is an apocalyptic number.

21011101210 is an abundant number, since it is smaller than the sum of its proper divisors (22674015782).

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

21011101210 is a wasteful number, since it uses less digits than its factorization.

21011101210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11235918.

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21011101210 its reverse (1210111012), we get a palindrome (22221212222).

It can be divided in two parts, 21011 and 101210, that added together give a palindrome (122221).

The spelling of 21011101210 in words is "twenty-one billion, eleven million, one hundred one thousand, two hundred ten".