21001321101 has 24 divisors (see below), whose sum is σ = 29707555584. Its totient is φ = 13182963840.

The previous prime is 21001321069. The next prime is 21001321111. The reversal of 21001321101 is 10112310012.

It is not a de Polignac number, because 21001321101 - 2⁵ = 21001321069 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001321111) 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 23 ways as a sum of consecutive naturals, for example, 44841 + ... + 209793.

It is an arithmetic number, because the mean of its divisors is an integer number (1237814816).

Almost surely, 2^21001321101 is an apocalyptic number.

It is an amenable number.

21001321101 is a deficient number, since it is larger than the sum of its proper divisors (8706234483).

21001321101 is a wasteful number, since it uses less digits than its factorization.

21001321101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165061 (or 165024 counting only the distinct ones).

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

Adding to 21001321101 its reverse (10112310012), we get a palindrome (31113631113).

The spelling of 21001321101 in words is "twenty-one billion, one million, three hundred twenty-one thousand, one hundred one".