2170856687 has 2 divisors, whose sum is σ = 2170856688. Its totient is φ = 2170856686.

The previous prime is 2170856671. The next prime is 2170856717. The reversal of 2170856687 is 7866580712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2170856687 - 2⁴ = 2170856671 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2170852687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1085428343 + 1085428344.

It is an arithmetic number, because the mean of its divisors is an integer number (1085428344).

Almost surely, 2^2170856687 is an apocalyptic number.

2170856687 is a deficient number, since it is larger than the sum of its proper divisors (1).

2170856687 is an equidigital number, since it uses as much as digits as its factorization.

2170856687 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1128960, while the sum is 50.

The square root of 2170856687 is about 46592.4531120653. The cubic root of 2170856687 is about 1294.8229384789.

The spelling of 2170856687 in words is "two billion, one hundred seventy million, eight hundred fifty-six thousand, six hundred eighty-seven".