21124101101 has 4 divisors (see below), whose sum is σ = 21125141952. Its totient is φ = 21123060252.

The previous prime is 21124101083. The next prime is 21124101109. The reversal of 21124101101 is 10110142112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21124101101 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21124101109) 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 3 ways as a sum of consecutive naturals, for example, 489365 + ... + 530778.

It is an arithmetic number, because the mean of its divisors is an integer number (5281285488).

Almost surely, 2^21124101101 is an apocalyptic number.

It is an amenable number.

21124101101 is a deficient number, since it is larger than the sum of its proper divisors (1040851).

21124101101 is a wasteful number, since it uses less digits than its factorization.

21124101101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1040850.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21124101101 its reverse (10110142112), we get a palindrome (31234243213).

The spelling of 21124101101 in words is "twenty-one billion, one hundred twenty-four million, one hundred one thousand, one hundred one".