21210341123 has 4 divisors (see below), whose sum is σ = 21210632760. Its totient is φ = 21210049488.

The previous prime is 21210341107. The next prime is 21210341137. The reversal of 21210341123 is 32114301212.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21210341123 - 2⁴ = 21210341107 is a prime.

It is a super-2 number, since 2×21210341123² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21210341095 and 21210341104.

It is not an unprimeable number, because it can be changed into a prime (21210341153) 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, 62036 + ... + 215102.

It is an arithmetic number, because the mean of its divisors is an integer number (5302658190).

Almost surely, 2^21210341123 is an apocalyptic number.

21210341123 is a deficient number, since it is larger than the sum of its proper divisors (291637).

21210341123 is a wasteful number, since it uses less digits than its factorization.

21210341123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291636.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 21210341123 its reverse (32114301212), we get a palindrome (53324642335).

The spelling of 21210341123 in words is "twenty-one billion, two hundred ten million, three hundred forty-one thousand, one hundred twenty-three".