21103121101 has 4 divisors (see below), whose sum is σ = 21103560352. Its totient is φ = 21102681852.

The previous prime is 21103121089. The next prime is 21103121131. The reversal of 21103121101 is 10112130112.

It is a happy number.

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 21103121101 - 2³¹ = 18955637453 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 (21103121131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 137265 + ... + 247078.

It is an arithmetic number, because the mean of its divisors is an integer number (5275890088).

Almost surely, 2^21103121101 is an apocalyptic number.

It is an amenable number.

21103121101 is a deficient number, since it is larger than the sum of its proper divisors (439251).

21103121101 is an equidigital number, since it uses as much as digits as its factorization.

21103121101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 439250.

The product of its (nonzero) digits is 12, while the sum is 13.

Adding to 21103121101 its reverse (10112130112), we get a palindrome (31215251213).

The spelling of 21103121101 in words is "twenty-one billion, one hundred three million, one hundred twenty-one thousand, one hundred one".