8721087785667 has 64 divisors (see below), whose sum is σ = 13748942592000. Its totient is φ = 5453737632000.

The previous prime is 8721087785651. The next prime is 8721087785701. The reversal of 8721087785667 is 7665877801278.

It is a happy number.

It is not a de Polignac number, because 8721087785667 - 2⁴ = 8721087785651 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 8721087785595 and 8721087785604.

It is not an unprimeable number, because it can be changed into a prime (8721087785617) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7104292 + ... + 8240942.

It is an arithmetic number, because the mean of its divisors is an integer number (214827228000).

Almost surely, 2^{8721087785667} is an apocalyptic number.

8721087785667 is a gapful number since it is divisible by the number (87) formed by its first and last digit.

8721087785667 is a deficient number, since it is larger than the sum of its proper divisors (5027854806333).

8721087785667 is a wasteful number, since it uses less digits than its factorization.

8721087785667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1136969 (or 1136963 counting only the distinct ones).

The product of its (nonzero) digits is 442552320, while the sum is 72.

The spelling of 8721087785667 in words is "eight trillion, seven hundred twenty-one billion, eighty-seven million, seven hundred eighty-five thousand, six hundred sixty-seven".