19681891682442 has 256 divisors, whose sum is σ = 46853937561600. Its totient is φ = 5448732157440.

The previous prime is 19681891682441. The next prime is 19681891682459. The reversal of 19681891682442 is 24428619818691.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (19681891682441) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 744864043 + ... + 744890465.

It is an arithmetic number, because the mean of its divisors is an integer number (183023193600).

Almost surely, 2^{19681891682442} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19681891682442, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23426968780800).

19681891682442 is an abundant number, since it is smaller than the sum of its proper divisors (27172045879158).

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

19681891682442 is a wasteful number, since it uses less digits than its factorization.

19681891682442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26713.

The product of its digits is 95551488, while the sum is 69.

The spelling of 19681891682442 in words is "nineteen trillion, six hundred eighty-one billion, eight hundred ninety-one million, six hundred eighty-two thousand, four hundred forty-two".