21210202423 has 8 divisors (see below), whose sum is σ = 21251985920. Its totient is φ = 21168446040.

The previous prime is 21210202421. The next prime is 21210202501. The reversal of 21210202423 is 32420201212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21210202423 - 2¹ = 21210202421 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21210202423.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210202421) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2271358 + ... + 2280676.

It is an arithmetic number, because the mean of its divisors is an integer number (2656498240).

Almost surely, 2^21210202423 is an apocalyptic number.

21210202423 is a deficient number, since it is larger than the sum of its proper divisors (41783497).

21210202423 is an equidigital number, since it uses as much as digits as its factorization.

21210202423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13557.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 21210202423 its reverse (32420201212), we get a palindrome (53630403635).

The spelling of 21210202423 in words is "twenty-one billion, two hundred ten million, two hundred two thousand, four hundred twenty-three".