21320434006351 has 8 divisors (see below), whose sum is σ = 21328315649024. Its totient is φ = 21312552713400.

The previous prime is 21320434006327. The next prime is 21320434006373. The reversal of 21320434006351 is 15360043402312.

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 not a de Polignac number, because 21320434006351 - 2¹⁵ = 21320433973583 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 (21320434006301) 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, 239642926 + ... + 239731876.

It is an arithmetic number, because the mean of its divisors is an integer number (2666039456128).

Almost surely, 2^{21320434006351} is an apocalyptic number.

21320434006351 is a deficient number, since it is larger than the sum of its proper divisors (7881642673).

21320434006351 is an equidigital number, since it uses as much as digits as its factorization.

21320434006351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174861.

The product of its (nonzero) digits is 51840, while the sum is 34.

Adding to 21320434006351 its reverse (15360043402312), we get a palindrome (36680477408663).

The spelling of 21320434006351 in words is "twenty-one trillion, three hundred twenty billion, four hundred thirty-four million, six thousand, three hundred fifty-one".