21840706013 has 4 divisors (see below), whose sum is σ = 24960806880. Its totient is φ = 18720605148.

The previous prime is 21840706003. The next prime is 21840706039. The reversal of 21840706013 is 31060704812.

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 de Polignac number, because none of the positive numbers 2^k-21840706013 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 (21840706003) 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, 1560050423 + ... + 1560050436.

It is an arithmetic number, because the mean of its divisors is an integer number (6240201720).

Almost surely, 2^21840706013 is an apocalyptic number.

It is an amenable number.

21840706013 is a deficient number, since it is larger than the sum of its proper divisors (3120100867).

21840706013 is an equidigital number, since it uses as much as digits as its factorization.

21840706013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3120100866.

The product of its (nonzero) digits is 8064, while the sum is 32.

The spelling of 21840706013 in words is "twenty-one billion, eight hundred forty million, seven hundred six thousand, thirteen".