21243001205 has 8 divisors (see below), whose sum is σ = 26833264800. Its totient is φ = 16099958736.

The previous prime is 21243001201. The next prime is 21243001229. The reversal of 21243001205 is 50210034212.

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 21243001205 - 2² = 21243001201 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21243001201) 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, 111805175 + ... + 111805364.

It is an arithmetic number, because the mean of its divisors is an integer number (3354158100).

Almost surely, 2^21243001205 is an apocalyptic number.

It is an amenable number.

21243001205 is a deficient number, since it is larger than the sum of its proper divisors (5590263595).

21243001205 is a wasteful number, since it uses less digits than its factorization.

21243001205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223610563.

The product of its (nonzero) digits is 480, while the sum is 20.

Adding to 21243001205 its reverse (50210034212), we get a palindrome (71453035417).

The spelling of 21243001205 in words is "twenty-one billion, two hundred forty-three million, one thousand, two hundred five".