21110213023 has 4 divisors (see below), whose sum is σ = 21110773120. Its totient is φ = 21109652928.

The previous prime is 21110213009. The next prime is 21110213057. The reversal of 21110213023 is 32031201112.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21110213023 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21110212988 and 21110213006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21110283023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 219090 + ... + 300367.

It is an arithmetic number, because the mean of its divisors is an integer number (5277693280).

Almost surely, 2^21110213023 is an apocalyptic number.

21110213023 is a deficient number, since it is larger than the sum of its proper divisors (560097).

21110213023 is an equidigital number, since it uses as much as digits as its factorization.

21110213023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 560096.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21110213023 its reverse (32031201112), we get a palindrome (53141414135).

The spelling of 21110213023 in words is "twenty-one billion, one hundred ten million, two hundred thirteen thousand, twenty-three".