21278590944 has 384 divisors, whose sum is σ = 65182537728. Its totient is φ = 6027141120.

The previous prime is 21278590933. The next prime is 21278590973. The reversal of 21278590944 is 44909587212.

It is a super-2 number, since 2×21278590944² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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 63 ways as a sum of consecutive naturals, for example, 108013054 + ... + 108013250.

It is an arithmetic number, because the mean of its divisors is an integer number (169746192).

Almost surely, 2^21278590944 is an apocalyptic number.

21278590944 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 21278590944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32591268864).

21278590944 is an abundant number, since it is smaller than the sum of its proper divisors (43903946784).

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

21278590944 is a wasteful number, since it uses less digits than its factorization.

21278590944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 370 (or 362 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 51.

The spelling of 21278590944 in words is "twenty-one billion, two hundred seventy-eight million, five hundred ninety thousand, nine hundred forty-four".