21423344351 has 2 divisors, whose sum is σ = 21423344352. Its totient is φ = 21423344350.

The previous prime is 21423344347. The next prime is 21423344357. The reversal of 21423344351 is 15344332412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21423344351 - 2² = 21423344347 is a prime.

It is a super-2 number, since 2×21423344351² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21423344357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10711672175 + 10711672176.

It is an arithmetic number, because the mean of its divisors is an integer number (10711672176).

Almost surely, 2^21423344351 is an apocalyptic number.

21423344351 is a deficient number, since it is larger than the sum of its proper divisors (1).

21423344351 is an equidigital number, since it uses as much as digits as its factorization.

21423344351 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34560, while the sum is 32.

Adding to 21423344351 its reverse (15344332412), we get a palindrome (36767676763).

The spelling of 21423344351 in words is "twenty-one billion, four hundred twenty-three million, three hundred forty-four thousand, three hundred fifty-one".