21877278384 has 160 divisors (see below), whose sum is σ = 61706050560. Its totient is φ = 6638920704.

The previous prime is 21877278377. The next prime is 21877278403. The reversal of 21877278384 is 48387277812.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17887597 + ... + 17888819.

It is an arithmetic number, because the mean of its divisors is an integer number (385662816).

Almost surely, 2^21877278384 is an apocalyptic number.

21877278384 is a gapful number since it is divisible by the number (24) 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 21877278384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30853025280).

21877278384 is an abundant number, since it is smaller than the sum of its proper divisors (39828772176).

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

21877278384 is a wasteful number, since it uses less digits than its factorization.

21877278384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1619 (or 1613 counting only the distinct ones).

The product of its digits is 8429568, while the sum is 57.

The spelling of 21877278384 in words is "twenty-one billion, eight hundred seventy-seven million, two hundred seventy-eight thousand, three hundred eighty-four".