80820566691840 has 416 divisors, whose sum is σ = 295092604114560. Its totient is φ = 20969655238656.

The previous prime is 80820566691769. The next prime is 80820566691869. The reversal of 80820566691840 is 4819666502808.

It is a super-4 number, since 4×80820566691840⁴ (a number of 57 digits) contains 4444 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 18484387 + ... + 22434653.

Almost surely, 2^{80820566691840} is an apocalyptic number.

80820566691840 is a gapful number since it is divisible by the number (80) 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 80820566691840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (147546302057280).

80820566691840 is an abundant number, since it is smaller than the sum of its proper divisors (214272037422720).

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

80820566691840 is a wasteful number, since it uses less digits than its factorization.

80820566691840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3950342 (or 3950314 counting only the distinct ones).

The product of its (nonzero) digits is 39813120, while the sum is 63.

The spelling of 80820566691840 in words is "eighty trillion, eight hundred twenty billion, five hundred sixty-six million, six hundred ninety-one thousand, eight hundred forty".