6720161687 has 2 divisors, whose sum is σ = 6720161688. Its totient is φ = 6720161686.

The previous prime is 6720161681. The next prime is 6720161711. The reversal of 6720161687 is 7861610276.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 6720161687 - 2⁴ = 6720161671 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6720161681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3360080843 + 3360080844.

It is an arithmetic number, because the mean of its divisors is an integer number (3360080844).

Almost surely, 2^6720161687 is an apocalyptic number.

6720161687 is a deficient number, since it is larger than the sum of its proper divisors (1).

6720161687 is an equidigital number, since it uses as much as digits as its factorization.

6720161687 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 169344, while the sum is 44.

The square root of 6720161687 is about 81976.5923114641. The cubic root of 6720161687 is about 1887.0927267232.

The spelling of 6720161687 in words is "six billion, seven hundred twenty million, one hundred sixty-one thousand, six hundred eighty-seven".