21000334251 has 8 divisors (see below), whose sum is σ = 30154326160. Its totient is φ = 12923282592.

The previous prime is 21000334241. The next prime is 21000334259. The reversal of 21000334251 is 15243300012.

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

It is not a de Polignac number, because 21000334251 - 2¹⁰ = 21000333227 is a prime.

It is a super-3 number, since 3×21000334251³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21000334259) 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, 269235016 + ... + 269235093.

It is an arithmetic number, because the mean of its divisors is an integer number (3769290770).

Almost surely, 2^21000334251 is an apocalyptic number.

21000334251 is a deficient number, since it is larger than the sum of its proper divisors (9153991909).

21000334251 is a wasteful number, since it uses less digits than its factorization.

21000334251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 538470125.

The product of its (nonzero) digits is 720, while the sum is 21.

Adding to 21000334251 its reverse (15243300012), we get a palindrome (36243634263).

The spelling of 21000334251 in words is "twenty-one billion, three hundred thirty-four thousand, two hundred fifty-one".