21214304251 has 8 divisors (see below), whose sum is σ = 25520967680. Its totient is φ = 17226652968.

The previous prime is 21214304239. The next prime is 21214304273. The reversal of 21214304251 is 15240341212.

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

It is not a de Polignac number, because 21214304251 - 2⁹ = 21214303739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21214304351) 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, 79752891 + ... + 79753156.

It is an arithmetic number, because the mean of its divisors is an integer number (3190120960).

Almost surely, 2^21214304251 is an apocalyptic number.

21214304251 is a deficient number, since it is larger than the sum of its proper divisors (4306663429).

21214304251 is a wasteful number, since it uses less digits than its factorization.

21214304251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159506073.

The product of its (nonzero) digits is 1920, while the sum is 25.

Adding to 21214304251 its reverse (15240341212), we get a palindrome (36454645463).

The spelling of 21214304251 in words is "twenty-one billion, two hundred fourteen million, three hundred four thousand, two hundred fifty-one".