21019770559440 has 200 divisors, whose sum is σ = 73023380990208. Its totient is φ = 5603843761920.

The previous prime is 21019770559387. The next prime is 21019770559477. The reversal of 21019770559440 is 4495507791012.

21019770559440 is a `hidden beast` number, since 2 + 1 + 0 + 1 + 9 + 7 + 7 + 0 + 5 + 594 + 40 = 666.

It is a super-2 number, since 2×21019770559440² (a number of 27 digits) contains 22 as substring.

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 (23) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 25139305 + ... + 25961975.

Almost surely, 2^{21019770559440} is an apocalyptic number.

21019770559440 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 21019770559440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36511690495104).

21019770559440 is an abundant number, since it is smaller than the sum of its proper divisors (52003610430768).

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

21019770559440 is a wasteful number, since it uses less digits than its factorization.

21019770559440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 826639 (or 826624 counting only the distinct ones).

The product of its (nonzero) digits is 3175200, while the sum is 54.

The spelling of 21019770559440 in words is "twenty-one trillion, nineteen billion, seven hundred seventy million, five hundred fifty-nine thousand, four hundred forty".