21551243343 has 8 divisors (see below), whose sum is σ = 32839989888. Its totient is φ = 12314996184.

The previous prime is 21551243279. The next prime is 21551243377. The reversal of 21551243343 is 34334215512.

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

It is not a de Polignac number, because 21551243343 - 2⁶ = 21551243279 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21551244343) 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, 513124821 + ... + 513124862.

It is an arithmetic number, because the mean of its divisors is an integer number (4104998736).

Almost surely, 2^21551243343 is an apocalyptic number.

21551243343 is a deficient number, since it is larger than the sum of its proper divisors (11288746545).

21551243343 is a wasteful number, since it uses less digits than its factorization.

21551243343 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1026249693.

The product of its digits is 43200, while the sum is 33.

Adding to 21551243343 its reverse (34334215512), we get a palindrome (55885458855).

The spelling of 21551243343 in words is "twenty-one billion, five hundred fifty-one million, two hundred forty-three thousand, three hundred forty-three".