21032123111 has 4 divisors (see below), whose sum is σ = 21032885400. Its totient is φ = 21031360824.

The previous prime is 21032123029. The next prime is 21032123171. The reversal of 21032123111 is 11132123012.

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-21032123111 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 21032123111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21032123171) 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, 338141 + ... + 395478.

It is an arithmetic number, because the mean of its divisors is an integer number (5258221350).

Almost surely, 2^21032123111 is an apocalyptic number.

21032123111 is a deficient number, since it is larger than the sum of its proper divisors (762289).

21032123111 is an equidigital number, since it uses as much as digits as its factorization.

21032123111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 762288.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 21032123111 its reverse (11132123012), we get a palindrome (32164246123).

Subtracting from 21032123111 its reverse (11132123012), we obtain a palindrome (9900000099).

The spelling of 21032123111 in words is "twenty-one billion, thirty-two million, one hundred twenty-three thousand, one hundred eleven".