8500721687 has 2 divisors, whose sum is σ = 8500721688. Its totient is φ = 8500721686.

The previous prime is 8500721683. The next prime is 8500721707. The reversal of 8500721687 is 7861270058.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 8500721687 - 2² = 8500721683 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8500721683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4250360843 + 4250360844.

It is an arithmetic number, because the mean of its divisors is an integer number (4250360844).

Almost surely, 2^8500721687 is an apocalyptic number.

8500721687 is a deficient number, since it is larger than the sum of its proper divisors (1).

8500721687 is an equidigital number, since it uses as much as digits as its factorization.

8500721687 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 188160, while the sum is 44.

The square root of 8500721687 is about 92199.3583871385. The cubic root of 8500721687 is about 2040.8853077050.

The spelling of 8500721687 in words is "eight billion, five hundred million, seven hundred twenty-one thousand, six hundred eighty-seven".