21782364583770 has 288 divisors, whose sum is σ = 69814549743120. Its totient is φ = 4689894021120.

The previous prime is 21782364583751. The next prime is 21782364583841. The reversal of 21782364583770 is 7738546328712.

It is a happy number.

21782364583770 is a `hidden beast` number, since 2 + 1 + 7 + 82 + 3 + 6 + 458 + 37 + 70 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 11732317011009 + 10050047572761 = 3425247^2 + 3170181^2 .

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 21782364583698 and 21782364583707.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 3166404 + ... + 7320576.

Almost surely, 2^{21782364583770} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21782364583770, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34907274871560).

21782364583770 is an abundant number, since it is smaller than the sum of its proper divisors (48032185159350).

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

21782364583770 is a wasteful number, since it uses less digits than its factorization.

21782364583770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4154270 (or 4154260 counting only the distinct ones).

The product of its (nonzero) digits is 94832640, while the sum is 63.

The spelling of 21782364583770 in words is "twenty-one trillion, seven hundred eighty-two billion, three hundred sixty-four million, five hundred eighty-three thousand, seven hundred seventy".