21318726028851 has 32 divisors (see below), whose sum is σ = 31600345088000. Its totient is φ = 14204814492960.

The previous prime is 21318726028849. The next prime is 21318726028861. The reversal of 21318726028851 is 15882062781312.

It is a happy number.

21318726028851 is a `hidden beast` number, since 2 + 13 + 18 + 7 + 2 + 602 + 8 + 8 + 5 + 1 = 666.

It is not a de Polignac number, because 21318726028851 - 2¹ = 21318726028849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21318726028811) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 565479600 + ... + 565517298.

It is an arithmetic number, because the mean of its divisors is an integer number (987510784000).

Almost surely, 2^{21318726028851} is an apocalyptic number.

21318726028851 is a deficient number, since it is larger than the sum of its proper divisors (10281619059149).

21318726028851 is a wasteful number, since it uses less digits than its factorization.

21318726028851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48456 (or 48450 counting only the distinct ones).

The product of its (nonzero) digits is 2580480, while the sum is 54.

The spelling of 21318726028851 in words is "twenty-one trillion, three hundred eighteen billion, seven hundred twenty-six million, twenty-eight thousand, eight hundred fifty-one".