21043112101 has 4 divisors (see below), whose sum is σ = 22956122304. Its totient is φ = 19130101900.

The previous prime is 21043112087. The next prime is 21043112107. The reversal of 21043112101 is 10121134012.

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 not a de Polignac number, because 21043112101 - 2²¹ = 21041014949 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21043112107) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 956505085 + ... + 956505106.

It is an arithmetic number, because the mean of its divisors is an integer number (5739030576).

Almost surely, 2^21043112101 is an apocalyptic number.

It is an amenable number.

21043112101 is a deficient number, since it is larger than the sum of its proper divisors (1913010203).

21043112101 is a wasteful number, since it uses less digits than its factorization.

21043112101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1913010202.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 21043112101 its reverse (10121134012), we get a palindrome (31164246113).

The spelling of 21043112101 in words is "twenty-one billion, forty-three million, one hundred twelve thousand, one hundred one".