21499435390680 has 1792 divisors, whose sum is σ = 84465864806400. Its totient is φ = 4875992432640.

The previous prime is 21499435390673. The next prime is 21499435390717. The reversal of 21499435390680 is 8609353499412.

21499435390680 is a `hidden beast` number, since 2 + 1 + 4 + 9 + 94 + 3 + 539 + 0 + 6 + 8 + 0 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 447 ways as a sum of consecutive naturals, for example, 89209275360 + ... + 89209275600.

It is an arithmetic number, because the mean of its divisors is an integer number (47134969200).

Almost surely, 2^{21499435390680} is an apocalyptic number.

21499435390680 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 21499435390680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42232932403200).

21499435390680 is an abundant number, since it is smaller than the sum of its proper divisors (62966429415720).

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

21499435390680 is a wasteful number, since it uses less digits than its factorization.

21499435390680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 536 (or 517 counting only the distinct ones).

The product of its (nonzero) digits is 50388480, while the sum is 63.

The spelling of 21499435390680 in words is "twenty-one trillion, four hundred ninety-nine billion, four hundred thirty-five million, three hundred ninety thousand, six hundred eighty".