21313212103 has 4 divisors (see below), whose sum is σ = 22566930480. Its totient is φ = 20059493728.

The previous prime is 21313212061. The next prime is 21313212169. The reversal of 21313212103 is 30121231312.

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-21313212103 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 (21313212803) 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, 626859163 + ... + 626859196.

It is an arithmetic number, because the mean of its divisors is an integer number (5641732620).

Almost surely, 2^21313212103 is an apocalyptic number.

21313212103 is a deficient number, since it is larger than the sum of its proper divisors (1253718377).

21313212103 is a wasteful number, since it uses less digits than its factorization.

21313212103 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1253718376.

The product of its (nonzero) digits is 216, while the sum is 19.

Adding to 21313212103 its reverse (30121231312), we get a palindrome (51434443415).

The spelling of 21313212103 in words is "twenty-one billion, three hundred thirteen million, two hundred twelve thousand, one hundred three".