21187278112 has 288 divisors, whose sum is σ = 56937517056. Its totient is φ = 7551498240.

The previous prime is 21187278107. The next prime is 21187278137.

21187278112 is nontrivially palindromic in base 10.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 55319073 + ... + 55319455.

It is an arithmetic number, because the mean of its divisors is an integer number (197699712).

Almost surely, 2^21187278112 is an apocalyptic number.

21187278112 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21187278112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28468758528).

21187278112 is an abundant number, since it is smaller than the sum of its proper divisors (35750238944).

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

21187278112 is a wasteful number, since it uses less digits than its factorization.

21187278112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 592 (or 573 counting only the distinct ones).

The product of its digits is 25088, while the sum is 40.

The spelling of 21187278112 in words is "twenty-one billion, one hundred eighty-seven million, two hundred seventy-eight thousand, one hundred twelve".