21596065937 has 4 divisors (see below), whose sum is σ = 21676348980. Its totient is φ = 21515782896.

The previous prime is 21596065919. The next prime is 21596065943. The reversal of 21596065937 is 73956069512.

It is a Cunningham number, because it is equal to 146956²+1.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1420988416 + 20175077521 = 37696^2 + 142039^2 .

It is a cyclic number.

It is not a de Polignac number, because 21596065937 - 2²⁴ = 21579288721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21596065987) 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, 40141118 + ... + 40141655.

It is an arithmetic number, because the mean of its divisors is an integer number (5419087245).

Almost surely, 2^21596065937 is an apocalyptic number.

It is an amenable number.

21596065937 is a deficient number, since it is larger than the sum of its proper divisors (80283043).

21596065937 is an equidigital number, since it uses as much as digits as its factorization.

21596065937 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80283042.

The product of its (nonzero) digits is 3061800, while the sum is 53.

The spelling of 21596065937 in words is "twenty-one billion, five hundred ninety-six million, sixty-five thousand, nine hundred thirty-seven".