210423404123221 has 4 divisors (see below), whose sum is σ = 211261744378944. Its totient is φ = 209585063867500.

The previous prime is 210423404123201. The next prime is 210423404123243. The reversal of 210423404123221 is 122321404324012.

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 210423404123221 - 2¹⁷ = 210423403992149 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 (210423404123201) 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, 419170127485 + ... + 419170127986.

It is an arithmetic number, because the mean of its divisors is an integer number (52815436094736).

Almost surely, 2^{210423404123221} is an apocalyptic number.

It is an amenable number.

210423404123221 is a deficient number, since it is larger than the sum of its proper divisors (838340255723).

210423404123221 is an equidigital number, since it uses as much as digits as its factorization.

210423404123221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 838340255722.

The product of its (nonzero) digits is 18432, while the sum is 31.

Adding to 210423404123221 its reverse (122321404324012), we get a palindrome (332744808447233).

The spelling of 210423404123221 in words is "two hundred ten trillion, four hundred twenty-three billion, four hundred four million, one hundred twenty-three thousand, two hundred twenty-one".