210221109923 has 4 divisors (see below), whose sum is σ = 229332119928. Its totient is φ = 191110099920.

The previous prime is 210221109893. The next prime is 210221109941. The reversal of 210221109923 is 329901122012.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 210221109923 - 2⁸ = 210221109667 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 210221109923.

It is not an unprimeable number, because it can be changed into a prime (210221109223) 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, 9555504986 + ... + 9555505007.

It is an arithmetic number, because the mean of its divisors is an integer number (57333029982).

Almost surely, 2^210221109923 is an apocalyptic number.

210221109923 is a deficient number, since it is larger than the sum of its proper divisors (19111010005).

210221109923 is a wasteful number, since it uses less digits than its factorization.

210221109923 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19111010004.

The product of its (nonzero) digits is 3888, while the sum is 32.

The spelling of 210221109923 in words is "two hundred ten billion, two hundred twenty-one million, one hundred nine thousand, nine hundred twenty-three".