21743908697 has 4 divisors (see below), whose sum is σ = 24850181376. Its totient is φ = 18637636020.

The previous prime is 21743908673. The next prime is 21743908763. The reversal of 21743908697 is 79680934712.

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 not a de Polignac number, because 21743908697 - 2³² = 17448941401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21743908297) 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, 1553136329 + ... + 1553136342.

It is an arithmetic number, because the mean of its divisors is an integer number (6212545344).

Almost surely, 2^21743908697 is an apocalyptic number.

It is an amenable number.

21743908697 is a deficient number, since it is larger than the sum of its proper divisors (3106272679).

21743908697 is an equidigital number, since it uses as much as digits as its factorization.

21743908697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3106272678.

The product of its (nonzero) digits is 4572288, while the sum is 56.

The spelling of 21743908697 in words is "twenty-one billion, seven hundred forty-three million, nine hundred eight thousand, six hundred ninety-seven".