21968661343 has 8 divisors (see below), whose sum is σ = 22528343376. Its totient is φ = 21411196800.

The previous prime is 21968661331. The next prime is 21968661397. The reversal of 21968661343 is 34316686912.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21968661343 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 (21968661443) 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, 534298 + ... + 573943.

It is an arithmetic number, because the mean of its divisors is an integer number (2816042922).

Almost surely, 2^21968661343 is an apocalyptic number.

21968661343 is a deficient number, since it is larger than the sum of its proper divisors (559682033).

21968661343 is a wasteful number, since it uses less digits than its factorization.

21968661343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1108745.

The product of its digits is 1119744, while the sum is 49.

The spelling of 21968661343 in words is "twenty-one billion, nine hundred sixty-eight million, six hundred sixty-one thousand, three hundred forty-three".