21301221011 has 16 divisors (see below), whose sum is σ = 24949478400. Its totient is φ = 17809841088.

The previous prime is 21301221001. The next prime is 21301221023. The reversal of 21301221011 is 11012210312.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21301221011 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21301221001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 186146 + ... + 277943.

It is an arithmetic number, because the mean of its divisors is an integer number (1559342400).

Almost surely, 2^21301221011 is an apocalyptic number.

21301221011 is a deficient number, since it is larger than the sum of its proper divisors (3648257389).

21301221011 is an equidigital number, since it uses as much as digits as its factorization.

21301221011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 464258.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21301221011 its reverse (11012210312), we get a palindrome (32313431323).

The spelling of 21301221011 in words is "twenty-one billion, three hundred one million, two hundred twenty-one thousand, eleven".