21001101311 has 16 divisors (see below), whose sum is σ = 21970206720. Its totient is φ = 20050908960.

The previous prime is 21001101307. The next prime is 21001101313. The reversal of 21001101311 is 11310110012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21001101311 - 2² = 21001101307 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21001101292 and 21001101301.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001101313) 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, 1983650 + ... + 1994208.

It is an arithmetic number, because the mean of its divisors is an integer number (1373137920).

Almost surely, 2^21001101311 is an apocalyptic number.

21001101311 is a deficient number, since it is larger than the sum of its proper divisors (969105409).

21001101311 is a wasteful number, since it uses less digits than its factorization.

21001101311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11446.

The product of its (nonzero) digits is 6, while the sum is 11.

Adding to 21001101311 its reverse (11310110012), we get a palindrome (32311211323).

The spelling of 21001101311 in words is "twenty-one billion, one million, one hundred one thousand, three hundred eleven".