687228161 has 2 divisors, whose sum is σ = 687228162. Its totient is φ = 687228160.

The previous prime is 687228137. The next prime is 687228169. The reversal of 687228161 is 161822786.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 687226225 + 1936 = 26215^2 + 44^2 .

It is a cyclic number.

It is not a de Polignac number, because 687228161 - 2¹⁰ = 687227137 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (687228169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343614080 + 343614081.

It is an arithmetic number, because the mean of its divisors is an integer number (343614081).

Almost surely, 2^687228161 is an apocalyptic number.

It is an amenable number.

687228161 is a deficient number, since it is larger than the sum of its proper divisors (1).

687228161 is an equidigital number, since it uses as much as digits as its factorization.

687228161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64512, while the sum is 41.

The square root of 687228161 is about 26215.0369253984. The cubic root of 687228161 is about 882.4707428768.

The spelling of 687228161 in words is "six hundred eighty-seven million, two hundred twenty-eight thousand, one hundred sixty-one".