21124040745 has 16 divisors (see below), whose sum is σ = 34205677632. Its totient is φ = 11130417600.

The previous prime is 21124040737. The next prime is 21124040747. The reversal of 21124040745 is 54704042112.

It is not a de Polignac number, because 21124040745 - 2³ = 21124040737 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21124040747) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8482306 + ... + 8484795.

It is an arithmetic number, because the mean of its divisors is an integer number (2137854852).

Almost surely, 2^21124040745 is an apocalyptic number.

It is an amenable number.

21124040745 is a deficient number, since it is larger than the sum of its proper divisors (13081636887).

21124040745 is a wasteful number, since it uses less digits than its factorization.

21124040745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16967192.

The product of its (nonzero) digits is 8960, while the sum is 30.

Adding to 21124040745 its reverse (54704042112), we get a palindrome (75828082857).

The spelling of 21124040745 in words is "twenty-one billion, one hundred twenty-four million, forty thousand, seven hundred forty-five".