21033242351 has 32 divisors (see below), whose sum is σ = 24355598400. Its totient is φ = 17981824000.

The previous prime is 21033242309. The next prime is 21033242381. The reversal of 21033242351 is 15324233012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21033242351 - 2¹⁸ = 21032980207 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21033242351.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21033242381) 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 in 31 ways as a sum of consecutive naturals, for example, 12306485 + ... + 12308193.

It is an arithmetic number, because the mean of its divisors is an integer number (761112450).

Almost surely, 2^21033242351 is an apocalyptic number.

21033242351 is a deficient number, since it is larger than the sum of its proper divisors (3322356049).

21033242351 is a wasteful number, since it uses less digits than its factorization.

21033242351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2731.

The product of its (nonzero) digits is 4320, while the sum is 26.

Adding to 21033242351 its reverse (15324233012), we get a palindrome (36357475363).

The spelling of 21033242351 in words is "twenty-one billion, thirty-three million, two hundred forty-two thousand, three hundred fifty-one".