21928995540 has 432 divisors, whose sum is σ = 75488474880. Its totient is φ = 5336513280.

The previous prime is 21928995533. The next prime is 21928995551. The reversal of 21928995540 is 4559982912.

21928995540 is a `hidden beast` number, since 2 + 1 + 9 + 2 + 8 + 9 + 95 + 540 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

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 143 ways as a sum of consecutive naturals, for example, 50879125 + ... + 50879555.

It is an arithmetic number, because the mean of its divisors is an integer number (174741840).

Almost surely, 2^21928995540 is an apocalyptic number.

21928995540 is a gapful number since it is divisible by the number (20) 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 21928995540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37744237440).

21928995540 is an abundant number, since it is smaller than the sum of its proper divisors (53559479340).

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

21928995540 is a wasteful number, since it uses less digits than its factorization.

21928995540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 522 (or 489 counting only the distinct ones).

The product of its (nonzero) digits is 2332800, while the sum is 54.

The spelling of 21928995540 in words is "twenty-one billion, nine hundred twenty-eight million, nine hundred ninety-five thousand, five hundred forty".