999577768680 has 448 divisors, whose sum is σ = 3498765138000. Its totient is φ = 256591577088.

The previous prime is 999577768649. The next prime is 999577768697. The reversal of 999577768680 is 86867775999.

It can be written as a sum of positive squares in 8 ways, for example, as 638806956516 + 360770812164 = 799254^2 + 600642^2 .

It is a Harshad number since it is a multiple of its sum of digits (81).

It is a self number, because there is not a number n which added to its sum of digits gives 999577768680.

It is an unprimeable number.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 315422136 + ... + 315425304.

Almost surely, 2^999577768680 is an apocalyptic number.

999577768680 is a gapful number since it is divisible by the number (90) 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 999577768680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1749382569000).

999577768680 is an abundant number, since it is smaller than the sum of its proper divisors (2499187369320).

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

999577768680 is a wasteful number, since it uses less digits than its factorization.

999577768680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3600 (or 3581 counting only the distinct ones).

The product of its (nonzero) digits is 2880541440, while the sum is 81.

The spelling of 999577768680 in words is "nine hundred ninety-nine billion, five hundred seventy-seven million, seven hundred sixty-eight thousand, six hundred eighty".