21243037005 has 24 divisors (see below), whose sum is σ = 36951396768. Its totient is φ = 11289578976.

The previous prime is 21243037003. The next prime is 21243037009. The reversal of 21243037005 is 50073034212.

It is not a de Polignac number, because 21243037005 - 2¹ = 21243037003 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21243037005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21243037003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 821307 + ... + 846776.

It is an arithmetic number, because the mean of its divisors is an integer number (1539641532).

Almost surely, 2^21243037005 is an apocalyptic number.

It is an amenable number.

21243037005 is a deficient number, since it is larger than the sum of its proper divisors (15708359763).

21243037005 is a wasteful number, since it uses less digits than its factorization.

21243037005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1668377 (or 1668374 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 27.

The spelling of 21243037005 in words is "twenty-one billion, two hundred forty-three million, thirty-seven thousand, five".