687228137 has 2 divisors, whose sum is σ = 687228138. Its totient is φ = 687228136.

The previous prime is 687228103. The next prime is 687228161. The reversal of 687228137 is 731822786.

It is a happy number.

687228137 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 508096681 + 179131456 = 22541^2 + 13384^2 .

It is a cyclic number.

It is not a de Polignac number, because 687228137 - 2¹⁰ = 687227113 is a prime.

It is not a weakly prime, because it can be changed into another prime (687228187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343614068 + 343614069.

It is an arithmetic number, because the mean of its divisors is an integer number (343614069).

Almost surely, 2^687228137 is an apocalyptic number.

It is an amenable number.

687228137 is a deficient number, since it is larger than the sum of its proper divisors (1).

687228137 is an equidigital number, since it uses as much as digits as its factorization.

687228137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 225792, while the sum is 44.

The square root of 687228137 is about 26215.0364676458. The cubic root of 687228137 is about 882.4707326040.

The spelling of 687228137 in words is "six hundred eighty-seven million, two hundred twenty-eight thousand, one hundred thirty-seven".