21051340907 has 8 divisors (see below), whose sum is σ = 22291170192. Its totient is φ = 19811680000.

The previous prime is 21051340867. The next prime is 21051340913. The reversal of 21051340907 is 70904315012.

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 21051340907 - 2¹⁴ = 21051324523 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21051340927) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 290432 + ... + 355602.

It is an arithmetic number, because the mean of its divisors is an integer number (2786396274).

Almost surely, 2^21051340907 is an apocalyptic number.

21051340907 is a deficient number, since it is larger than the sum of its proper divisors (1239829285).

21051340907 is a wasteful number, since it uses less digits than its factorization.

21051340907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84189.

The product of its (nonzero) digits is 7560, while the sum is 32.

Adding to 21051340907 its reverse (70904315012), we get a palindrome (91955655919).

The spelling of 21051340907 in words is "twenty-one billion, fifty-one million, three hundred forty thousand, nine hundred seven".