21144235451 has 8 divisors (see below), whose sum is σ = 21734133744. Its totient is φ = 20555307360.

The previous prime is 21144235433. The next prime is 21144235459. The reversal of 21144235451 is 15453244112.

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 21144235451 - 2¹⁰ = 21144234427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21144235459) 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, 198245 + ... + 285638.

It is an arithmetic number, because the mean of its divisors is an integer number (2716766718).

Almost surely, 2^21144235451 is an apocalyptic number.

21144235451 is a deficient number, since it is larger than the sum of its proper divisors (589898293).

21144235451 is a wasteful number, since it uses less digits than its factorization.

21144235451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485101.

The product of its digits is 19200, while the sum is 32.

Adding to 21144235451 its reverse (15453244112), we get a palindrome (36597479563).

The spelling of 21144235451 in words is "twenty-one billion, one hundred forty-four million, two hundred thirty-five thousand, four hundred fifty-one".