21310212101 has 4 divisors (see below), whose sum is σ = 21360830604. Its totient is φ = 21259593600.

The previous prime is 21310212083. The next prime is 21310212139. The reversal of 21310212101 is 10121201312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6999832225 + 14310379876 = 83665^2 + 119626^2 .

It is a cyclic number.

It is not a de Polignac number, because 21310212101 - 2²² = 21306017797 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 (21310212601) 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, 25308620 + ... + 25309461.

It is an arithmetic number, because the mean of its divisors is an integer number (5340207651).

Almost surely, 2^21310212101 is an apocalyptic number.

It is an amenable number.

21310212101 is a deficient number, since it is larger than the sum of its proper divisors (50618503).

21310212101 is an equidigital number, since it uses as much as digits as its factorization.

21310212101 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50618502.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 21310212101 its reverse (10121201312), we get a palindrome (31431413413).

The spelling of 21310212101 in words is "twenty-one billion, three hundred ten million, two hundred twelve thousand, one hundred one".