21276801018 has 96 divisors (see below), whose sum is σ = 52556055552. Its totient is φ = 6163466400.

The previous prime is 21276801011. The next prime is 21276801023. The reversal of 21276801018 is 81010867212.

It is not an unprimeable number, because it can be changed into a prime (21276801011) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 373573 + ... + 426743.

It is an arithmetic number, because the mean of its divisors is an integer number (547458912).

Almost surely, 2^21276801018 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21276801018, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26278027776).

21276801018 is an abundant number, since it is smaller than the sum of its proper divisors (31279254534).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21276801018 is a wasteful number, since it uses less digits than its factorization.

21276801018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53280 (or 53277 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 36.

The spelling of 21276801018 in words is "twenty-one billion, two hundred seventy-six million, eight hundred one thousand, eighteen".