21203234413 has 4 divisors (see below), whose sum is σ = 21296640960. Its totient is φ = 21109827868.

The previous prime is 21203234407. The next prime is 21203234417. The reversal of 21203234413 is 31443230212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21203234413 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 (21203234417) 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, 46702933 + ... + 46703386.

It is an arithmetic number, because the mean of its divisors is an integer number (5324160240).

Almost surely, 2^21203234413 is an apocalyptic number.

It is an amenable number.

21203234413 is a deficient number, since it is larger than the sum of its proper divisors (93406547).

21203234413 is an equidigital number, since it uses as much as digits as its factorization.

21203234413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93406546.

The product of its (nonzero) digits is 3456, while the sum is 25.

Adding to 21203234413 its reverse (31443230212), we get a palindrome (52646464625).

The spelling of 21203234413 in words is "twenty-one billion, two hundred three million, two hundred thirty-four thousand, four hundred thirteen".