605688021 has 6 divisors (see below), whose sum is σ = 874882710. Its totient is φ = 403792008.

The previous prime is 605688001. The next prime is 605688037. The reversal of 605688021 is 120886506.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 319908996 + 285779025 = 17886^2 + 16905^2 .

It is not a de Polignac number, because 605688021 - 2⁵ = 605687989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (605688001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 33649326 + ... + 33649343.

It is an arithmetic number, because the mean of its divisors is an integer number (145813785).

Almost surely, 2^605688021 is an apocalyptic number.

It is an amenable number.

605688021 is a deficient number, since it is larger than the sum of its proper divisors (269194689).

605688021 is a wasteful number, since it uses less digits than its factorization.

605688021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67298675 (or 67298672 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 605688021 is about 24610.7297941365. The cubic root of 605688021 is about 846.0895441996.

The spelling of 605688021 in words is "six hundred five million, six hundred eighty-eight thousand, twenty-one".