21213110123 has 8 divisors (see below), whose sum is σ = 21361237920. Its totient is φ = 21065083200.

The previous prime is 21213110053. The next prime is 21213110141. The reversal of 21213110123 is 32101131212.

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 21213110123 - 2¹² = 21213106027 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21213110423) 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, 424661 + ... + 471977.

It is an arithmetic number, because the mean of its divisors is an integer number (2670154740).

Almost surely, 2^21213110123 is an apocalyptic number.

21213110123 is a deficient number, since it is larger than the sum of its proper divisors (148127797).

21213110123 is a wasteful number, since it uses less digits than its factorization.

21213110123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50437.

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

Adding to 21213110123 its reverse (32101131212), we get a palindrome (53314241335).

The spelling of 21213110123 in words is "twenty-one billion, two hundred thirteen million, one hundred ten thousand, one hundred twenty-three".