687909133 has 2 divisors, whose sum is σ = 687909134. Its totient is φ = 687909132.

The previous prime is 687909121. The next prime is 687909161. The reversal of 687909133 is 331909786.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 685025929 + 2883204 = 26173^2 + 1698^2 .

It is a cyclic number.

It is not a de Polignac number, because 687909133 - 2²⁹ = 151038221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (687909533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343954566 + 343954567.

It is an arithmetic number, because the mean of its divisors is an integer number (343954567).

Almost surely, 2^687909133 is an apocalyptic number.

It is an amenable number.

687909133 is a deficient number, since it is larger than the sum of its proper divisors (1).

687909133 is an equidigital number, since it uses as much as digits as its factorization.

687909133 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 244944, while the sum is 46.

The square root of 687909133 is about 26228.0219040628. The cubic root of 687909133 is about 882.7621257202.

The spelling of 687909133 in words is "six hundred eighty-seven million, nine hundred nine thousand, one hundred thirty-three".