66840011826 has 96 divisors (see below), whose sum is σ = 162044634240. Its totient is φ = 18303715584.

The previous prime is 66840011813. The next prime is 66840011857. The reversal of 66840011826 is 62811004866.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1139451 + ... + 1196673.

It is an arithmetic number, because the mean of its divisors is an integer number (1687964940).

Almost surely, 2^66840011826 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66840011826, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81022317120).

66840011826 is an abundant number, since it is smaller than the sum of its proper divisors (95204622414).

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

66840011826 is a wasteful number, since it uses less digits than its factorization.

66840011826 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57408 (or 57401 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 42.

The spelling of 66840011826 in words is "sixty-six billion, eight hundred forty million, eleven thousand, eight hundred twenty-six".