816077221680 has 960 divisors, whose sum is σ = 3179962183680. Its totient is φ = 169083002880.

The previous prime is 816077221643. The next prime is 816077221693. The reversal of 816077221680 is 86122770618.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 3595053727 + ... + 3595053953.

It is an arithmetic number, because the mean of its divisors is an integer number (3312460608).

Almost surely, 2^816077221680 is an apocalyptic number.

816077221680 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 816077221680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1589981091840).

816077221680 is an abundant number, since it is smaller than the sum of its proper divisors (2363884962000).

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

816077221680 is a wasteful number, since it uses less digits than its factorization.

816077221680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418 (or 371 counting only the distinct ones).

The product of its (nonzero) digits is 451584, while the sum is 48.

The spelling of 816077221680 in words is "eight hundred sixteen billion, seventy-seven million, two hundred twenty-one thousand, six hundred eighty".